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98-589: The letters FSRA could refer to: FsrA , a type of RNA. Financial Services Regulatory Authority of Ontario , a Crown agency responsible for oversight of the financial industry in Ontario, Canada. Formula Sidecar Racing Association , the association administering sidecar racing in the United Kingdom. Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

196-685: A silage additive under Schedule IV-Part 2-Class 8.6 and assigned the International Feed Ingredient number IFN 8-19-119. On the other hand, several feed additives containing viable spores of B. subtilis have been positively evaluated by the European Food Safety Authority , regarding their safe use for weight gaining in animal production. Bacillus subtilis spores can survive the extreme heat generated during cooking. Some B. subtilis strains are responsible for causing ropiness or rope spoilage –

294-465: A 2014 study from McGill University in Montreal, Canada which suggests that mice handled by men rather than women showed higher stress levels. Another study in 2016 suggested that gut microbiomes in mice may have an impact upon scientific research. Ethical concerns, as well as the cost, maintenance and relative inefficiency of animal research has encouraged development of alternative methods for

392-578: A healthy gut flora and vitamin K 2 intake; during this long history of widespread use, natto has not been implicated in adverse events potentially attributable to the presence of B. subtilis . The natto product and the B. subtilis natto as its principal component are FOSHU (Foods for Specified Health Use) approved by the Japanese Ministry of Health, Labour, and Welfare as effective for preservation of health. Bacillus subtilis has been granted "Qualified Presumption of Safety" status by

490-528: A laboratory model organism, B. subtilis is often considered as the Gram-positive equivalent of Escherichia coli , an extensively studied Gram-negative bacterium. Colony, morphological, physiological, and biochemical characteristics of Bacillus subtilis are shown in the Table below. Note: + = Positive, – =Negative This species is commonly found in the upper layers of the soil and B. subtilis

588-591: A local review board called the Institutional Animal Care and Use Committee (IACUC). All laboratory experiments involving living animals are reviewed and approved by this committee. In addition to proving the potential for benefit to human health, minimization of pain and distress, and timely and humane euthanasia, experimenters must justify their protocols based on the principles of Replacement, Reduction and Refinement. "Replacement" refers to efforts to engage alternatives to animal use. This includes

686-406: A lower total neutrophil fraction in the blood , a lower neutrophil enzymatic capacity, lower activity of the complement system , and a different set of pentraxins involved in the inflammatory process ; and lack genes for important components of the immune system, such as IL-8 , IL-37 , TLR10 , ICAM-3 , etc. Laboratory mice reared in specific-pathogen-free (SPF) conditions usually have

784-547: A model for neuronal development by Sydney Brenner in 1963, and has been extensively used in many different contexts since then. C. elegans was the first multicellular organism whose genome was completely sequenced, and as of 2012, the only organism to have its connectome (neuronal "wiring diagram") completed. Arabidopsis thaliana is currently the most popular model plant. Its small stature and short generation time facilitates rapid genetic studies, and many phenotypic and biochemical mutants have been mapped. A. thaliana

882-666: A nearly transparent body during early development, which provides unique visual access to the animal's internal anatomy during this time period. Zebrafish are used to study development, toxicology and toxicopathology, specific gene function and roles of signaling pathways. Other important model organisms and some of their uses include: T4 phage (viral infection), Tetrahymena thermophila (intracellular processes), maize ( transposons ), hydras ( regeneration and morphogenesis ), cats (neurophysiology), chickens (development), dogs (respiratory and cardiovascular systems), Nothobranchius furzeri (aging), non-human primates such as

980-551: A portal from which to download sequences (DNA, RNA, or protein) or to access functional information on specific genes, for example the sub-cellular localization of the gene product or its physiological role. Many animal models serving as test subjects in biomedical research, such as rats and mice, may be selectively sedentary , obese and glucose intolerant . This may confound their use to model human metabolic processes and diseases as these can be affected by dietary energy intake and exercise . Similarly, there are differences between

1078-541: A positive amylase activity and high heat resistance. B. subtilis CU1 (2 × 10 spores per day) was evaluated in a 16-week study (10 days administration of probiotic, followed by 18 days wash-out period per each month; repeated same procedure for total 4 months) to healthy subjects. B. subtilis CU1 was found to be safe and well tolerated in the subjects without any side effects. Bacillus subtilis and substances derived from it have been evaluated by different authoritative bodies for their safe and beneficial use in food. In

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1176-521: A process replication in a multi-step fashion, the researchers can simultaneously carry on the interactions of these added molecules to interact with enzymes and other molecules used for a secondary reaction by treating it like a capsule, which is similar to how the bacteria performs its own DNA replication processes. Cultures of B. subtilis were popular worldwide, before the introduction of antibiotics , as an immunostimulatory agent to aid treatment of gastrointestinal and urinary tract diseases. It

1274-588: A rather immature immune system with a deficit of memory T cells . These mice may have limited diversity of the microbiota , which directly affects the immune system and the development of pathological conditions. Moreover, persistent virus infections (for example, herpesviruses ) are activated in humans, but not in SPF mice, with septic complications and may change the resistance to bacterial coinfections . “Dirty” mice are possibly better suitable for mimicking human pathologies. In addition, inbred mouse strains are used in

1372-401: A single endospore that can remain viable for decades and is resistant to unfavourable environmental conditions such as drought , salinity , extreme pH , radiation , and solvents . The endospore is formed at times of nutritional stress and through the use of hydrolysis, allowing the organism to persist in the environment until conditions become favourable. Prior to the process of sporulation

1470-550: A sticky, stringy consistency caused by bacterial production of long-chain polysaccharides  – in spoiled bread dough and baked goods. For a long time, bread ropiness was associated uniquely with B. subtilis species by biochemical tests. Molecular assays (randomly amplified polymorphic DNA PCR assay, denaturing gradient gel electrophoresis analysis, and sequencing of the V3 region of 16S ribosomal DNA ) revealed greater Bacillus species variety in ropy breads, which all seems to have

1568-407: A type I restriction modification system endonuclease, are able to act as recipients of conjugative plasmids in mating experiments, paving the way for further genetic engineering of this particular B. subtilis strain. By adopting Green Chemistry in the use of less hazardous materials, while saving cost, researchers have been mimicking nature's methods of synthesizing chemicals that can be useful for

1666-468: A unicellular green alga with well-studied genetics, is used to study photosynthesis and motility . C. reinhardtii has many known and mapped mutants and expressed sequence tags, and there are advanced methods for genetic transformation and selection of genes. Dictyostelium discoideum is used in molecular biology and genetics , and is studied as an example of cell communication , differentiation , and programmed cell death . Among invertebrates,

1764-506: A wide variety of experimental techniques and goals from many different levels of biology—from ecology , behavior and biomechanics , down to the tiny functional scale of individual tissues , organelles and proteins . Inquiries about the DNA of organisms are classed as genetic models (with short generation times, such as the fruitfly and nematode worm), experimental models, and genomic parsimony models, investigating pivotal position in

1862-548: A wider assortment of lineages on the tree of life . The primary reason for the use of model organisms in research is the evolutionary principle that all organisms share some degree of relatedness and genetic similarity due to common ancestry . The study of taxonomic human relatives, then, can provide a great deal of information about mechanism and disease within the human body that can be useful in medicine. Various phylogenetic trees for vertebrates have been constructed using comparative proteomics , genetics, genomics as well as

1960-412: Is Escherichia coli ( E. coli ), which has been intensively investigated for over 60 years. It is a common, gram-negative gut bacterium which can be grown and cultured easily and inexpensively in a laboratory setting. It is the most widely used organism in molecular genetics , and is an important species in the fields of biotechnology and microbiology , where it has served as the host organism for

2058-446: Is a facultative anaerobe and had been considered as an obligate aerobe until 1998. B. subtilis is heavily flagellated , which gives it the ability to move quickly in liquids. B. subtilis has proven highly amenable to genetic manipulation , and has become widely adopted as a model organism for laboratory studies, especially of sporulation , which is a simplified example of cellular differentiation . In terms of popularity as

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2156-415: Is a facultative anaerobe . B. subtilis is considered the best studied Gram-positive bacterium and a model organism to study bacterial chromosome replication and cell differentiation. It is one of the bacterial champions in secreted enzyme production and used on an industrial scale by biotechnology companies. Bacillus subtilis is a Gram-positive bacterium, rod-shaped and catalase -positive. It

2254-406: Is constantly replaced so it continues to inhibit sporulation. When the full chromosome localizes to the forespore, spoIIAB can repress sigma F. Therefore, the genetic asymmetry of the B. subtilis chromosome and expression of sigma F, spoIIAB and spoIIAA dictate spore formation in B. subtilis. Bacillus subtilis is a model organism used to study bacterial chromosome replication. Replication of

2352-439: Is difficult to build an animal model that perfectly reproduces the symptoms of depression in patients. Depression, as other mental disorders , consists of endophenotypes that can be reproduced independently and evaluated in animals. An ideal animal model offers an opportunity to understand molecular , genetic and epigenetic factors that may lead to depression. By using animal models, the underlying molecular alterations and

2450-409: Is encoded by spoIIAA. SpoIIAA is located near the locus for the sigma factor, so it is consistently expressed in the forespore. Since the spoIIAB locus is not located near the sigma F and spoIIAA loci, it is expressed only in the mother cell and therefore repress sporulation in that cell, allowing sporulation to continue in the forespore. Residual spoIIAA in the mother cell represses spoIIAB, but spoIIAB

2548-437: Is evidence that B. subtilis is saprophytic in nature. Studies have shown that the bacterium exhibits vegetative growth in soil rich in organic matter, and that spores were formed when nutrients were depleted. Additionally, B. subtilis has been shown to form biofilms on plant roots, which might explain why it is commonly found in gut microbiomes. Perhaps animals eating plants with B. subtilis biofilms can foster growth of

2646-416: Is in the mother cell, the chromosome fragment in the forespore contains the locus for sigma F, which begins to be expressed in the forespore. In order to prevent sigma F expression in the mother cell, an anti-sigma factor, which is encoded by spoIIAB, is expressed. Any residual anti-sigma factor in the forespore (which would otherwise interfere with sporulation) is inhibited by an anti-anti-sigma factor, which

2744-645: Is no substitute for a living organism when studying complex interactions in disease pathology or treatments. Debate about the ethical use of animals in research dates at least as far back as 1822 when the British Parliament under pressure from British and Indian intellectuals enacted the first law for animal protection preventing cruelty to cattle. This was followed by the Cruelty to Animals Act of 1835 and 1849, which criminalized ill-treating, over-driving, and torturing animals. In 1876, under pressure from

2842-431: Is no useful in vitro model system available. Model organisms are drawn from all three domains of life, as well as viruses . One of the first model systems for molecular biology was the bacterium Escherichia coli ( E. coli ), a common constituent of the human digestive system. The mouse ( Mus musculus ) has been used extensively as a model organism and is associated with many important biological discoveries of

2940-412: Is often more than a third of the total chromosome length of 4,215 kb. It appears that about 7–9% of the recipient cells take up an entire chromosome. In order for a recipient bacterium to bind, take up exogenous DNA from another bacterium of the same species and recombine it into its chromosome, it must enter a special physiological state called competence . Competence in B. subtilis is induced toward

3038-420: Is particularly useful as a toxicology model, and as a neurological model and source of primary cell cultures, owing to the larger size of organs and suborganellar structures relative to the mouse, while eggs and embryos from Xenopus tropicalis and Xenopus laevis (African clawed frog) are used in developmental biology, cell biology, toxicology, and neuroscience. Likewise, the zebrafish ( Danio rerio ) has

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3136-479: Is similar to a human condition. These test conditions are often termed as animal models of disease . The use of animal models allows researchers to investigate disease states in ways which would be inaccessible in a human patient, performing procedures on the non-human animal that imply a level of harm that would not be considered ethical to inflict on a human. The best models of disease are similar in etiology (mechanism of cause) and phenotype (signs and symptoms) to

3234-496: Is studied, again, because it is easy to grow for an animal, has various visible congenital traits and has a polytene (giant) chromosome in its salivary glands that can be examined under a light microscope. The roundworm Caenorhabditis elegans is studied because it has very defined development patterns involving fixed numbers of cells, and it can be rapidly assayed for abnormalities. Animal models serving in research may have an existing, inbred or induced disease or injury that

3332-773: Is then extracted from the medium using chemical processes. Since the 1960s B. subtilis has had a history as a test species in spaceflight experimentation. Its endospores can survive up to 6 years in space if coated by dust particles protecting it from solar UV rays. It has been used as an extremophile survival indicator in outer space such as Exobiology Radiation Assembly , EXOSTACK , and EXPOSE orbital missions. Wild-type natural isolates of B. subtilis are difficult to work with compared to laboratory strains that have undergone domestication processes of mutagenesis and selection. These strains often have improved capabilities of transformation (uptake and integration of environmental DNA), growth, and loss of abilities needed "in

3430-466: Is thought to be a normal gut commensal in humans. A 2009 study compared the density of spores found in soil (about 10 spores per gram) to that found in human feces (about 10 spores per gram). The number of spores found in the human gut was too high to be attributed solely to consumption through food contamination. In some bee habitats, B. subtilis appears in the gut flora of honey bees . B. subtilis can also be found in marine environments. There

3528-419: Is thought to still be present there. The antibiotic bacitracin was first isolated from a variety of Bacillus licheniformis named "Tracy I" in 1945, then considered part of the B. subtilis species. It is still commercially manufactured by growing the variety in a container of liquid growth medium . Over time, the bacteria synthesizes bacitracin and secretes the antibiotic into the medium. The bacitracin

3626-477: Is used with the aim of solving medical problems such as Alzheimer's disease, AIDS, multiple sclerosis, spinal cord injury, many headaches, and other conditions in which there is no useful in vitro model system available. Models are those organisms with a wealth of biological data that make them attractive to study as examples for other species and/or natural phenomena that are more difficult to study directly. Continual research on these organisms focuses on

3724-948: The B. subtilis genome in 2009, including Bsr RNAs . Microarray-based comparative genomic analyses have revealed that B. subtilis members show considerable genomic diversity. FsrA is a small RNA found in Bacillus subtilis . It is an effector of the iron sparing response, and acts to down-regulate iron-containing proteins in times of poor iron bioavailability. A promising fish probiotic, Bacillus subtilis strain WS1A, that possesses antimicrobial activity against Aeromonas veronii and suppressed motile Aeromonas septicemia in Labeo rohita . The de novo assembly resulted in an estimated chromosome size of 4,148,460 bp, with 4,288 open reading frames. B. subtilis strain WS1A genome contains many potential genes, such as those encoding proteins involved in

3822-421: The European Food Safety Authority . Model organism Research using animal models has been central to most of the achievements of modern medicine. It has contributed most of the basic knowledge in fields such as human physiology and biochemistry , and has played significant roles in fields such as neuroscience and infectious disease . The results have included the near- eradication of polio and

3920-515: The National Anti-Vivisection Society , the Cruelty to Animals Act was amended to include regulations governing the use of animals in research. This new act stipulated that 1) experiments must be proven absolutely necessary for instruction, or to save or prolong human life; 2) animals must be properly anesthetized; and 3) animals must be killed as soon as the experiment is over. Today, these three principles are central to

4018-410: The fruit fly Drosophila melanogaster is famous as the subject of genetics experiments by Thomas Hunt Morgan and others. They are easily raised in the lab, with rapid generations, high fecundity , few chromosomes , and easily induced observable mutations. The nematode Caenorhabditis elegans is used for understanding the genetic control of development and physiology. It was first proposed as

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4116-465: The hay bacillus or grass bacillus , is a gram-positive , catalase -positive bacterium , found in soil and the gastrointestinal tract of ruminants , humans and marine sponges. As a member of the genus Bacillus , B. subtilis is rod-shaped, and can form a tough, protective endospore , allowing it to tolerate extreme environmental conditions. B. subtilis has historically been classified as an obligate aerobe , though evidence exists that it

4214-622: The rhesus macaque and chimpanzee ( hepatitis , HIV , Parkinson's disease , cognition , and vaccines ), and ferrets ( SARS-CoV-2 ) The organisms below have become model organisms because they facilitate the study of certain characters or because of their genetic accessibility. For example, E. coli was one of the first organisms for which genetic techniques such as transformation or genetic manipulation has been developed. The genomes of all model species have been sequenced , including their mitochondrial / chloroplast genomes. Model organism databases exist to provide researchers with

4312-561: The 20th and 21st centuries. Other examples include baker's yeast ( Saccharomyces cerevisiae ), the T4 phage virus, the fruit fly Drosophila melanogaster , the flowering plant Arabidopsis thaliana , and guinea pigs ( Cavia porcellus ). Several of the bacterial viruses ( bacteriophage ) that infect E. coli also have been very useful for the study of gene structure and gene regulation (e.g. phages Lambda and T4 ). Disease models are divided into three categories: homologous animals have

4410-549: The DBA ("dilute, brown and non-agouti") inbred mouse strain and the systematic generation of other inbred strains. The mouse has since been used extensively as a model organism and is associated with many important biological discoveries of the 20th and 21st centuries. In the late 19th century, Emil von Behring isolated the diphtheria toxin and demonstrated its effects in guinea pigs. He went on to develop an antitoxin against diphtheria in animals and then in humans, which resulted in

4508-622: The United States by 1965. It has been estimated that developing and producing the vaccines required the use of 100,000 rhesus monkeys, with 65 doses of vaccine produced from each monkey. Sabin wrote in 1992, "Without the use of animals and human beings, it would have been impossible to acquire the important knowledge needed to prevent much suffering and premature death not only among humans, but also among animals." Other 20th-century medical advances and treatments that relied on research performed in animals include organ transplant techniques,

4606-508: The United States, an opinion letter issued in the early 1960s by the Food and Drug Administration (FDA) designated some substances derived from microorganisms as generally recognized as safe (GRAS), including carbohydrase and protease enzymes from B. subtilis . The opinions were predicated on the use of nonpathogenic and nontoxicogenic strains of the respective organisms and on the use of current good manufacturing practices. The FDA stated that

4704-430: The United States. Subsequent research in model organisms led to further medical advances, such as Frederick Banting 's research in dogs, which determined that the isolates of pancreatic secretion could be used to treat dogs with diabetes . This led to the 1922 discovery of insulin (with John Macleod ) and its use in treating diabetes, which had previously meant death. John Cade 's research in guinea pigs discovered

4802-438: The anticonvulsant properties of lithium salts, which revolutionized the treatment of bipolar disorder , replacing the previous treatments of lobotomy or electroconvulsive therapy. Modern general anaesthetics, such as halothane and related compounds, were also developed through studies on model organisms, and are necessary for modern, complex surgical operations. In the 1940s, Jonas Salk used rhesus monkey studies to isolate

4900-436: The bacterium in their gastrointestinal tract. It has been shown that the entire lifecycle of B. subtilis can be completed in the gastrointestinal tract, which provides credence to the idea that the bacterium enters the gut via plant consumption and stays present as a result of its ability to grow in the gut. Bacillus subtilis can divide symmetrically to make two daughter cells (binary fission), or asymmetrically, producing

4998-457: The basic knowledge in fields such as human physiology and biochemistry , and has played significant roles in fields such as neuroscience and infectious disease . For example, the results have included the near- eradication of polio and the development of organ transplantation , and have benefited both humans and animals. From 1910 to 1927, Thomas Hunt Morgan 's work with the fruit fly Drosophila melanogaster identified chromosomes as

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5096-447: The biosynthesis of riboflavin , vitamin B6 , and amino acids ( ilvD ) and in carbon utilization ( pta ). Natural bacterial transformation involves the transfer of DNA from one bacterium to another through the surrounding medium. In B. subtilis the length of transferred DNA is greater than 1,271 kb (more than 1 million bases). The transferred DNA is likely double-stranded DNA and

5194-420: The causal relationship between genetic or environmental alterations and depression can be examined, which would afford a better insight into pathology of depression. In addition, animal models of depression are indispensable for identifying novel therapies for depression. Model organisms are drawn from all three domains of life, as well as viruses . The most widely studied prokaryotic model organism

5292-410: The cells might become motile by producing flagella , take up DNA from the environment, or produce antibiotics . These responses are viewed as attempts to seek out nutrients by seeking a more favourable environment, enabling the cell to make use of new beneficial genetic material or simply by killing off competition. Under stressful conditions, such as nutrient deprivation, B. subtilis undergoes

5390-521: The conclusion that competence, with uptake of DNA, is specifically induced by DNA-damaging conditions, and that transformation functions as a process for recombinational repair of DNA damage. While the natural competent state is common within laboratory B. subtilis and field isolates, some industrially relevant strains, e.g. B. subtilis (natto), are reluctant to DNA uptake due to the presence of restriction modification systems that degrade exogenous DNA. B. subtilis (natto) mutants, which are defective in

5488-427: The development of organ transplantation , and have benefited both humans and animals. From 1910 to 1927, Thomas Hunt Morgan 's work with the fruit fly Drosophila melanogaster identified chromosomes as the vector of inheritance for genes, and Eric Kandel wrote that Morgan's discoveries "helped transform biology into an experimental science". Research in model organisms led to further medical advances, such as

5586-458: The diversity in the mechanisms and strategies that various bacterial species have adopted to carry out the duplication of their genomes. Bacillus subtilis has about 4,100 genes. Of these, only 192 were shown to be indispensable; another 79 were predicted to be essential, as well. A vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in

5684-423: The end of logarithmic growth, especially under conditions of amino-acid limitation. Under these stressful conditions of semistarvation, cells typically have just one copy of their chromosome and likely have increased DNA damage. To test whether transformation is an adaptive function for B. subtilis to repair its DNA damage, experiments were conducted using UV light as the damaging agent. These experiments led to

5782-534: The enzymes derived from the B. subtilis strain were in common use in food prior to January 1, 1958, and that nontoxigenic and nonpathogenic strains of B. subtilis are widely available and have been safely used in a variety of food applications. This includes consumption of Japanese fermented soy bean, in the form of Natto , which is commonly consumed in Japan, and contains as many as 10 viable cells per gram. The fermented beans are recognized for their contribution to

5880-533: The evolutionary tree. Historically, model organisms include a handful of species with extensive genomic research data, such as the NIH model organisms. Often, model organisms are chosen on the basis that they are amenable to experimental manipulation. This usually will include characteristics such as short life-cycle , techniques for genetic manipulation ( inbred strains, stem cell lines, and methods of transformation ) and non-specialist living requirements. Sometimes,

5978-455: The first to perform experiments on living animals. Discoveries in the 18th and 19th centuries included Antoine Lavoisier 's use of a guinea pig in a calorimeter to prove that respiration was a form of combustion, and Louis Pasteur 's demonstration of the germ theory of disease in the 1880s using anthrax in sheep. Research using animal models has been central to most of the achievements of modern medicine. It has contributed most of

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6076-622: The food and drug industry, by "piggybacking molecules on shorts strands of DNA" before they are zipped together during their complementary base pairing between the two strands. Each strand will carry a particular molecule of interest that will undergo a specific chemical reaction simultaneously when the two corresponding strands of DNA pairs hold together like a zipper, allowing another molecule of interest, to react with one another in controlled and isolated reaction between those molecules being carried into these DNA complementary attachments. By using this method with certain bacteria that naturally follow

6174-550: The genome arrangement facilitates the sequencing of the model organism's genome, for example, by being very compact or having a low proportion of junk DNA (e.g. yeast , arabidopsis , or pufferfish ). When researchers look for an organism to use in their studies, they look for several traits. Among these are size, generation time , accessibility, manipulation, genetics, conservation of mechanisms, and potential economic benefit. As comparative molecular biology has become more common, some researchers have sought model organisms from

6272-430: The geochemical and fossil record. These estimations tell us that humans and chimpanzees last shared a common ancestor about 6 million years ago (mya). As our closest relatives, chimpanzees have a lot of potential to tell us about mechanisms of disease (and what genes may be responsible for human intelligence). However, chimpanzees are rarely used in research and are protected from highly invasive procedures. Rodents are

6370-563: The guidance of animal models. Treatments for animal diseases have also been developed, including for rabies , anthrax , glanders , feline immunodeficiency virus (FIV), tuberculosis , Texas cattle fever, classical swine fever (hog cholera), heartworm , and other parasitic infections . Animal experimentation continues to be required for biomedical research, and is used with the aim of solving medical problems such as Alzheimer's disease, AIDS, multiple sclerosis, spinal cord injury, many headaches, and other conditions in which there

6468-540: The heart-lung machine, antibiotics , and the whooping cough vaccine. In researching human disease , model organisms allow for better understanding the disease process without the added risk of harming an actual human. The species of the model organism is usually chosen so that it reacts to disease or its treatment in a way that resembles human physiology , even though care must be taken when generalizing from one organism to another. However, many drugs, treatments and cures for human diseases are developed in part with

6566-428: The heart-lung machine, antibiotics , and the whooping cough vaccine. Treatments for animal diseases have also been developed, including for rabies , anthrax , glanders , feline immunodeficiency virus (FIV), tuberculosis , Texas cattle fever, classical swine fever (hog cholera), heartworm , and other parasitic infections . Animal experimentation continues to be required for biomedical research, and

6664-412: The host cells for propagation. In eukaryotes , several yeasts, particularly Saccharomyces cerevisiae ("baker's" or "budding" yeast), have been widely used in genetics and cell biology , largely because they are quick and easy to grow. The cell cycle in a simple yeast is very similar to the cell cycle in humans and is regulated by homologous proteins. The fruit fly Drosophila melanogaster

6762-904: The human equivalent. However complex human diseases can often be better understood in a simplified system in which individual parts of the disease process are isolated and examined. For instance, behavioral analogues of anxiety or pain in laboratory animals can be used to screen and test new drugs for the treatment of these conditions in humans. A 2000 study found that animal models concorded (coincided on true positives and false negatives) with human toxicity in 71% of cases, with 63% for nonrodents alone and 43% for rodents alone. In 1987, Davidson et al. suggested that selection of an animal model for research be based on nine considerations. These include 1) appropriateness as an analog, 2) transferability of information, 3) genetic uniformity of organisms, where applicable, 4) background knowledge of biological properties, 5) cost and availability, 6) generalizability of

6860-621: The immune systems of model organisms and humans that lead to significantly altered responses to stimuli, although the underlying principles of genome function may be the same. The impoverished environments inside standard laboratory cages deny research animals of the mental and physical challenges are necessary for healthy emotional development. Without day-to-day variety, risks and rewards, and complex environments, some have argued that animal models are irrelevant models of human experience. Mice differ from humans in several immune properties: mice are more resistant to some toxins than humans; have

6958-408: The laboratory. Some examples include: Spontaneous models refer to diseases that are analogous to human conditions that occur naturally in the animal being studied. These models are rare, but informative. Negative models essentially refer to control animals, which are useful for validating an experimental result. Orphan models refer to diseases for which there is no human analog and occur exclusively in

7056-598: The laws and guidelines governing the use of animals and research. In the U.S., the Animal Welfare Act of 1970 (see also Laboratory Animal Welfare Act ) set standards for animal use and care in research. This law is enforced by APHIS's Animal Care program. In academic settings in which NIH funding is used for animal research, institutions are governed by the NIH Office of Laboratory Animal Welfare (OLAW). At each site, OLAW guidelines and standards are upheld by

7154-412: The majority of work with recombinant DNA . Simple model eukaryotes include baker's yeast ( Saccharomyces cerevisiae ) and fission yeast ( Schizosaccharomyces pombe ), both of which share many characters with higher cells, including those of humans. For instance, many cell division genes that are critical for the development of cancer have been discovered in yeast. Chlamydomonas reinhardtii ,

7252-479: The modern methods of immunization and largely ended diphtheria as a threatening disease. The diphtheria antitoxin is famously commemorated in the Iditarod race, which is modeled after the delivery of antitoxin in the 1925 serum run to Nome . The success of animal studies in producing the diphtheria antitoxin has also been attributed as a cause for the decline of the early 20th-century opposition to animal research in

7350-550: The most common animal models. Phylogenetic trees estimate that humans and rodents last shared a common ancestor ~80-100mya. Despite this distant split, humans and rodents have far more similarities than they do differences. This is due to the relative stability of large portions of the genome, making the use of vertebrate animals particularly productive. Genomic data is used to make close comparisons between species and determine relatedness. Humans share about 99% of their genome with chimpanzees (98.7% with bonobos) and over 90% with

7448-497: The most virulent forms of the polio virus, which led to his creation of a polio vaccine . The vaccine, which was made publicly available in 1955, reduced the incidence of polio 15-fold in the United States over the following five years. Albert Sabin improved the vaccine by passing the polio virus through animal hosts, including monkeys; the Sabin vaccine was produced for mass consumption in 1963, and had virtually eradicated polio in

7546-436: The mouse. With so much of the genome conserved across species, it is relatively impressive that the differences between humans and mice can be accounted for in approximately six thousand genes (of ~30,000 total). Scientists have been able to take advantage of these similarities in generating experimental and predictive models of human disease. There are many model organisms. One of the first model systems for molecular biology

7644-454: The overwhelming majority of studies, while the human population is heterogeneous, pointing to the importance of studies in interstrain hybrid, outbred , and nonlinear mice. Some studies suggests that inadequate published data in animal testing may result in irreproducible research, with missing details about how experiments are done omitted from published papers or differences in testing that may introduce bias. Examples of hidden bias include

7742-420: The process of sporulation . This process has been very well studied and has served as a model organism for studying sporulation. Once B. subtilis commits to sporulation, the sigma factor sigma F is secreted. This factor promotes sporulation. A sporulation septum is formed and a chromosome is slowly moved into the forespore. When a third of one chromosome copy is in the forespore and the remaining two thirds

7840-451: The production of the diphtheria antitoxin and the 1922 discovery of insulin and its use in treating diabetes, which had previously meant death. Modern general anaesthetics such as halothane were also developed through studies on model organisms, and are necessary for modern, complex surgical operations. Other 20th-century medical advances and treatments that relied on research performed in animals include organ transplant techniques,

7938-505: The results, 7) ease of and adaptability to experimental manipulation, 8) ecological consequences, and 9) ethical implications. Animal models can be classified as homologous, isomorphic or predictive. Animal models can also be more broadly classified into four categories: 1) experimental, 2) spontaneous, 3) negative, 4) orphan. Experimental models are most common. These refer to models of disease that resemble human conditions in phenotype or response to treatment but are induced artificially in

8036-476: The same causes, symptoms and treatment options as would humans who have the same disease, isomorphic animals share the same symptoms and treatments, and predictive models are similar to a particular human disease in only a couple of aspects, but are useful in isolating and making predictions about mechanisms of a set of disease features. The use of animals in research dates back to ancient Greece , with Aristotle (384–322 BCE) and Erasistratus (304–258 BCE) among

8134-652: The similar Korean food cheonggukjang . Bacillus subtilis was reviewed by the US FDA Center for Veterinary Medicine and found to present no safety concerns when used in direct-fed microbial products, so the Association of American Feed Control Officials has listed it approved for use as an animal feed ingredient under Section 36.14 "Direct-fed Microorganisms". The Canadian Food Inspection Agency Animal Health and Production Feed Section has classified Bacillus culture dehydrated approved feed ingredients as

8232-505: The single circular chromosome initiates at a single locus, the origin ( oriC ). Replication proceeds bidirectionally and two replication forks progress in clockwise and counterclockwise directions along the chromosome. Chromosome replication is completed when the forks reach the terminus region, which is positioned opposite to the origin on the chromosome map . The terminus region contains several short DNA sequences ( Ter sites) that promote replication arrest. Specific proteins mediate all

8330-469: The species studied. The increase in knowledge of the genomes of non-human primates and other mammals that are genetically close to humans is allowing the production of genetically engineered animal tissues, organs and even animal species which express human diseases, providing a more robust model of human diseases in an animal model. Animal models observed in the sciences of psychology and sociology are often termed animal models of behavior . It

8428-492: The steps in DNA replication. Comparison between the proteins involved in chromosomal DNA replication in B. subtilis and in Escherichia coli reveals similarities and differences. Although the basic components promoting initiation, elongation, and termination of replication are well- conserved , some important differences can be found (such as one bacterium missing proteins essential in the other). These differences underline

8526-581: The study of disease. Cell culture, or in vitro studies, provide an alternative that preserves the physiology of the living cell, but does not require the sacrifice of an animal for mechanistic studies. Human, inducible pluripotent stem cells can also elucidate new mechanisms for understanding cancer and cell regeneration. Imaging studies (such as MRI or PET scans) enable non-invasive study of human subjects. Recent advances in genetics and genomics can identify disease-associated genes, which can be targeted for therapies. Many biomedical researchers argue that there

8624-469: The synthesis of cell envelope and the determination of cell shape and division, and one-tenth related to cell energetics. The complete genome sequence of B. subtilis sub-strain QB928 has 4,146,839 DNA base pairs and 4,292 genes. The QB928 strain is widely used in genetic studies due to the presence of various markers [aroI(aroK)906 purE1 dal(alrA)1 trpC2]. Several noncoding RNAs have been characterized in

8722-539: The title FSRA . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=FSRA&oldid=946329659 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages FsrA Bacillus subtilis ( / b ə ˈ s ɪ l . ə s s u b ˈ t iː . l i s / ), known also as

8820-491: The use of computer models, non-living tissues and cells, and replacement of “higher-order” animals (primates and mammals) with “lower” order animals (e.g. cold-blooded animals, invertebrates) wherever possible. "Reduction" refers to efforts to minimize number of animals used during the course of an experiment, as well as prevention of unnecessary replication of previous experiments. To satisfy this requirement, mathematical calculations of statistical power are employed to determine

8918-483: The vector of inheritance for genes. Drosophila became one of the first, and for some time the most widely used, model organisms, and Eric Kandel wrote that Morgan's discoveries "helped transform biology into an experimental science". D. melanogaster remains one of the most widely used eukaryotic model organisms. During the same time period, studies on mouse genetics in the laboratory of William Ernest Castle in collaboration with Abbie Lathrop led to generation of

9016-432: The wild". And, while dozens of different strains fitting this description exist, the strain designated '168' is the most widely used. Strain 168 is a tryptophan auxotroph isolated after X-ray mutagenesis of B. subtilis Marburg strain and is widely used in research due to its high transformation efficiency. Bacillus globigii , a closely related but phylogenetically distinct species now known as Bacillus atrophaeus

9114-459: Was marketed throughout America and Europe from 1946 as an immunostimulatory aid in the treatment of gut and urinary tract diseases such as Rotavirus and Shigellosis . In 1966, the U.S. Army dumped bacillus subtilis onto the grates of New York City subway stations for five days in order to observe how a biological agent dispensed around the subway trains would disperse and potentially affect unsuspecting passengers. Due to its ability to survive, it

9212-588: Was originally named Vibrio subtilis by Christian Gottfried Ehrenberg , and renamed Bacillus subtilis by Ferdinand Cohn in 1872 (subtilis being the Latin for "fine, thin, slender"). B. subtilis cells are typically rod-shaped, and are about 4–10 micrometers (μm) long and 0.25–1.0 μm in diameter, with a cell volume of about 4.6 fL at stationary phase. As with other members of the genus Bacillus , it can form an endospore , to survive extreme environmental conditions of temperature and desiccation. B. subtilis

9310-417: Was the bacterium Escherichia coli , a common constituent of the human digestive system. Several of the bacterial viruses ( bacteriophage ) that infect E. coli also have been very useful for the study of gene structure and gene regulation (e.g. phages Lambda and T4 ). However, it is debated whether bacteriophages should be classified as organisms, because they lack metabolism and depend on functions of

9408-569: Was the first plant to have its genome sequenced . Among vertebrates , guinea pigs ( Cavia porcellus ) were used by Robert Koch and other early bacteriologists as a host for bacterial infections, becoming a byword for "laboratory animal", but are less commonly used today. The classic model vertebrate is currently the mouse ( Mus musculus ). Many inbred strains exist, as well as lines selected for particular traits, often of medical interest, e.g. body size, obesity, muscularity, and voluntary wheel-running behavior. The rat ( Rattus norvegicus )

9506-460: Was used as a biowarfare simulant during Project SHAD (aka Project 112 ). Subsequent genomic analysis showed that the strains used in those studies were products of deliberate enrichment for strains that exhibited abnormally high rates of sporulation . A strain of B. subtilis formerly known as Bacillus natto is used in the commercial production of the Japanese food nattō , as well as

9604-435: Was used throughout the 1950s as an alternative medicine , which upon digestion has been found to significantly stimulate broad-spectrum immune activity including activation of secretion of specific antibodies IgM , IgG and IgA and release of CpG dinucleotides inducing interferon IFN-α / IFNγ producing activity of leukocytes and cytokines important in the development of cytotoxicity towards tumor cells . It

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