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54-460: MRSA ST398 is a strain of the gram-positive bacterium Staphylococcus aureus , which belongs to the genus Staphylococcus . This genus covers a large group of gram-positive bacteria that are classified taxonomically in the family Staphylococcaceae , order Bacillales , class Bacilli, and phylum Firmicutes. MRSA ST398, a new strain of MRSA, was first found in 2003, in Dutch hospitals. The bacteria

108-399: A cytoplasmic membrane and an outer cell membrane; they contain only a thin layer of peptidoglycan (2–3 nm) between these membranes. The presence of inner and outer cell membranes defines a new compartment in these cells: the periplasmic space or the periplasmic compartment. These bacteria have been designated as diderm bacteria . The distinction between the monoderm and diderm bacteria

162-560: A monograph in 1890 on the bactericidal effects of a solution that he christened " pyoktanin ", which was probably a mixture of aniline dyes similar to gentian violet. He set up a collaboration with E. Merck & Co. to market "Pyoktanin caeruleum" as an antiseptic. In 1902, Drigalski and Conradi found that although crystal violet inhibited the growth of many bacteria, it has little effect on Bacillus coli ( Escherichia coli ) and Bacillus typhi ( Salmonella typhi ), which are both gram-negative bacteria . A much more detailed study of

216-621: A monophyletic clade and that no loss of the outer membrane from any species from this group has occurred. In the classical sense, six gram-positive genera are typically pathogenic in humans. Two of these, Streptococcus and Staphylococcus , are cocci (sphere-shaped). The remaining organisms are bacilli (rod-shaped) and can be subdivided based on their ability to form spores . The non-spore formers are Corynebacterium and Listeria (a coccobacillus), whereas Bacillus and Clostridium produce spores. The spore-forming bacteria can again be divided based on their respiration : Bacillus

270-409: A more complex staining method, sensitivity can be improved further to 8 ng of DNA. When crystal violet is used as an alternative to fluorescent stains , it is not necessary to use ultraviolet illumination; this has made crystal violet popular as a means of avoiding UV-induced DNA destruction when performing DNA cloning in vitro . In biomedical research , crystal violet can be used to stain

324-429: A nontoxic DNA stain as an alternative to fluorescent , intercalating dyes such as ethidium bromide . Used in this manner, it may be either incorporated into the agarose gel or applied after the electrophoresis process is finished. Used at a 0.001% concentration and allowed to stain a gel after electrophoresis for 30 minutes, it can detect as little as 16  ng of DNA. Through use of a methyl orange counterstain and

378-972: A number of bacterial taxa (viz. Negativicutes , Fusobacteriota , Synergistota , and Elusimicrobiota ) that are either part of the phylum Bacillota or branch in its proximity are found to possess a diderm cell structure. However, a conserved signature indel (CSI) in the HSP60 ( GroEL ) protein distinguishes all traditional phyla of gram-negative bacteria (e.g., Pseudomonadota , Aquificota , Chlamydiota , Bacteroidota , Chlorobiota , " Cyanobacteria ", Fibrobacterota , Verrucomicrobiota , Planctomycetota , Spirochaetota , Acidobacteriota , etc.) from these other atypical diderm bacteria, as well as other phyla of monoderm bacteria (e.g., Actinomycetota , Bacillota , Thermotogota , Chloroflexota , etc.). The presence of this CSI in all sequenced species of conventional LPS ( lipopolysaccharide )-containing gram-negative bacterial phyla provides evidence that these phyla of bacteria form

432-793: A recipient host bacterium). In transformation, the genetic material passes through the intervening medium, and uptake is completely dependent on the recipient bacterium. As of 2014 about 80 species of bacteria were known to be capable of transformation, about evenly divided between gram-positive and gram-negative bacteria ; the number might be an overestimate since several of the reports are supported by single papers. Transformation among gram-positive bacteria has been studied in medically important species such as Streptococcus pneumoniae , Streptococcus mutans , Staphylococcus aureus and Streptococcus sanguinis and in gram-positive soil bacteria Bacillus subtilis and Bacillus cereus . The adjectives gram-positive and gram-negative derive from

486-508: A single membrane, but stain gram-negative due to either lack of the peptidoglycan layer, as in the mycoplasmas , or their inability to retain the Gram stain because of their cell wall composition—also show close relationship to the gram-positive bacteria. For the bacterial cells bounded by a single cell membrane, the term monoderm bacteria has been proposed. In contrast to gram-positive bacteria, all typical gram-negative bacteria are bounded by

540-443: A strongly acidic solution (pH −1.0), the dye is yellow with an absorption maximum at 420 nm. The different colours are a result of the different charged states of the dye molecule. In the yellow form, all three nitrogen atoms carry a positive charge, of which two are protonated , while the green colour corresponds to a form of the dye with two of the nitrogen atoms positively charged. At neutral pH, both extra protons are lost to

594-455: A surface layer called an S-layer . In gram-positive bacteria, the S-layer is attached to the peptidoglycan layer. Gram-negative bacteria's S-layer is attached directly to the outer membrane . Specific to gram-positive bacteria is the presence of teichoic acids in the cell wall. Some of these are lipoteichoic acids, which have a lipid component in the cell membrane that can assist in anchoring

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648-406: A zoonotic agent, MRSA ST398 can be transmitted from animal to human, human to animals, and human to human, which is an important factor when considering mitigation protocol. Transmission of MRSA ST398 is similar to that of MRSA. MRSA ST398 has an enhanced biofilm formation ability, which increases the survivability of the bacteria and increases its virulence. This increases the fitness of MRSA ST398 in

702-465: Is oxidized to the coloured cationic form (hereafter with oxygen , but a typical oxidizing agent is manganese dioxide , MnO 2 ): When dissolved in water, the dye has a blue-violet colour with an absorbance maximum at 590 nm and an extinction coefficient of 87,000 M  cm . The colour of the dye depends on the acidity of the solution. At a pH of +1.0, the dye is green with absorption maxima at 420 nm and 620 nm, while in

756-402: Is a facultative anaerobe , while Clostridium is an obligate anaerobe . Also, Rathybacter , Leifsonia , and Clavibacter are three gram-positive genera that cause plant disease. Gram-positive bacteria are capable of causing serious and sometimes fatal infections in newborn infants. Novel species of clinically relevant gram-positive bacteria also include Catabacter hongkongensis , which

810-550: Is a triarylmethane dye used as a histological stain and in Gram's method of classifying bacteria. Crystal violet has antibacterial , antifungal , and anthelmintic ( vermicide ) properties and was formerly important as a topical antiseptic . The medical use of the dye has been largely superseded by more modern drugs, although it is still listed by the World Health Organization . The name gentian violet

864-556: Is also known as "pyoctanin" (or "pyoctanine"). It is commonly used for: In resource-limited settings, gentian violet is used to manage burn wounds, inflammation of the umbilical cord stump ( omphalitis ) in the neonatal period, oral candidiasis in HIV -infected patients and mouth ulcers in children with measles . In body piercing , gentian violet is commonly used to mark the location for placing piercings, including surface piercings . Because of its antimicrobial activity, it

918-428: Is ambiguous as it refers to three distinct aspects (staining result, envelope organization, taxonomic group), which do not necessarily coalesce for some bacterial species. The gram-positive and gram-negative staining response is also not a reliable characteristic as these two kinds of bacteria do not form phylogenetic coherent groups. However, although Gram staining response is an empirical criterion, its basis lies in

972-427: Is an emerging pathogen belonging to Bacillota . Transformation is one of three processes for horizontal gene transfer , in which exogenous genetic material passes from a donor bacterium to a recipient bacterium, the other two processes being conjugation (transfer of genetic material between two bacterial cells in direct contact) and transduction (injection of donor bacterial DNA by a bacteriophage virus into

1026-426: Is because the thick layer of peptidoglycan in the bacterial cell wall retains the stain after it is washed away from the rest of the sample, in the decolorization stage of the test. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization step; alcohol used in this stage degrades the outer membrane of gram-negative cells, making the cell wall more porous and incapable of retaining

1080-504: Is important to reduce the burden of the pathogen in hospital settings. This also included closer observation of people who are in close contact with livestock, as early diagnoses can allow for earlier treatment. This is especially important, as antibiotics cannot be successful in antibiotic resistant bacteria. And an increased use of antibiotics further promotes the evolution of antibiotic resistant bacteria. And specifically in MRSA ST398,

1134-407: Is supported by conserved signature indels in a number of important proteins (viz. DnaK, GroEL). Of these two structurally distinct groups of bacteria, monoderms are indicated to be ancestral. Based upon a number of observations including that the gram-positive bacteria are the major producers of antibiotics and that, in general, gram-negative bacteria are resistant to them, it has been proposed that

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1188-526: Is thought to have been introduced by the German pharmacist Georg Grübler, who in 1880 started a company in Leipzig that specialized in the sale of staining reagents for histology . The gentian violet stain marketed by Grübler probably contained a mixture of methylated pararosaniline dyes. The stain proved popular and in 1884 was used by Hans Christian Gram to stain bacteria. He credited Paul Ehrlich for

1242-421: Is used by microbiologists to place bacteria into two main categories, Gram-positive (+) and Gram-negative (-). Gram-positive bacteria have a thick layer of peptidoglycan within the cell wall, and Gram-negative bacteria have a thin layer of peptidoglycan. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through an optical microscope . This

1296-530: Is used to treat ich in fish. However, it usually is illegal to use in fish intended for human consumption. Crystal violet is one of the components of methyl violet , a dye first synthesized by Charles Lauth in 1861. From 1866, methyl violet was manufactured by the Saint-Denis -based firm of Poirrier et Chappat and marketed under the name "Violet de Paris". It was a mixture of the tetra-, penta- and hexamethylated pararosanilines . Crystal violet itself

1350-484: The Biological Stain Commission appointed a committee chaired by Harold Conn to look into the suitability of the different commercial products. In his book Biological Stains , Conn describes gentian violet as a "poorly defined mixture of violet rosanilins ". The German ophthalmologist Jakob Stilling is credited with discovering the antiseptic properties of gentian violet. He published

1404-612: The US (FDA) has determined that gentian violet has not been shown by adequate scientific data to be safe for use in animal feed. Use of gentian violet in animal feed causes the feed to be adulterated and is a violation of the Federal Food, Drug, and Cosmetic Act in the US. On June 28, 2007, the FDA issued an "import alert" on farm raised seafood from China because unapproved antimicrobials, including gentian violet, had been consistently found in

1458-418: The absence of the outer membrane. In general, the following characteristics are present in gram-positive bacteria: Only some species have a capsule , usually consisting of polysaccharides . Also, only some species are flagellates , and when they do have flagella , have only two basal body rings to support them, whereas gram-negative have four. Both gram-positive and gram-negative bacteria commonly have

1512-443: The aniline-gentian violet mixture. Grübler's gentian violet was probably very similar, if not identical, to Lauth's methyl violet, which had been used as a stain by Victor André Cornil in 1875. Although the name gentian violet continued to be used for the histological stain, the name was not used in the dye and textile industries. The composition of the stain was not defined and different suppliers used different mixtures. In 1922,

1566-501: The archetypical diderm bacteria where the outer cell membrane contains lipopolysaccharide, and the diderm bacteria where outer cell membrane is made up of mycolic acid . In general, gram-positive bacteria are monoderms and have a single lipid bilayer whereas gram-negative bacteria are diderms and have two bilayers. Exceptions include: Some Bacillota species are not gram-positive. The class Negativicutes, which includes Selenomonas , are diderm and stain gram-negative. Additionally,

1620-506: The community and even in the healthcare settings, which poses a severe threat to public health. MRSA ST398 infection symptoms are similar to those of other MRSA infections. This includes skin infections, abscesses , sores , and pneumonia . In severe cases, MRSA ST98 can lead to sepsis and death. Patient education is a critical component of treatment and prevention. Clinicians are encouraged to educate patients, caregivers , and household members on methods to limit further spread of MRSA in

1674-567: The community. This includes maintaining adequate hygiene and keeping wounds covered with clean, dry bandages. Infected persons should also be excluded from activities that involve close contact with others. Before treatment, prevention is incredibly important to prevent the spread of the MRSA strain. This involves practicing good hygiene and infection control measures, particularly in healthcare settings and for those who work closely with livestock. An increased study of MRSA ST398, especially in livestock,

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1728-413: The crystal violet stain. Their peptidoglycan layer is much thinner and sandwiched between an inner cell membrane and a bacterial outer membrane , causing them to take up the counterstain ( safranin or fuchsine ) and appear red or pink. Despite their thicker peptidoglycan layer, gram-positive bacteria are more receptive to certain cell wall –targeting antibiotics than gram-negative bacteria, due to

1782-496: The effects of Grübler's gentian violet on different strains of bacteria was published by John Churchman in 1912. He found that most gram-positive bacteria (tainted) were sensitive to the dye, while most gram-negative bacteria (not tainted) were not, and observed that the dye tended to act as a bacteriostatic agent rather than a bactericide . One study in mice demonstrated dose-related carcinogenic potential at several different organ sites. The Food and Drug Administration in

1836-468: The gram-positive bacteria was challenged, with major implications for the therapeutic and general study of these organisms. Based on molecular studies of the 16S sequences, Woese recognised twelve bacterial phyla . Two of these were gram-positive and were divided on the proportion of the guanine and cytosine content in their DNA . The high G + C phylum was made up of the Actinobacteria , and

1890-471: The kingdom Monera was divided into four divisions based primarily on Gram staining: Bacillota (positive in staining), Gracilicutes (negative in staining), Mollicutes (neutral in staining) and Mendocutes (variable in staining). Based on 16S ribosomal RNA phylogenetic studies of the late microbiologist Carl Woese and collaborators and colleagues at the University of Illinois , the monophyly of

1944-481: The link between antibiotic use in livestock and the emergence of MRSA ST398 is not yet fully understood. Furthermore, a OneHeath approach should be implemented, which brings together multiple disciplines in policy; advocacy; animal, human, and environmental health, and more to tackle a public health issue. MRSA ST398 is resistant to many antimicrobial agents; therefore, treatment options for this strain are limited. However, hospitalization and aggressive treatment to treat

1998-626: The low G + C phylum contained the Firmicutes . The Actinomycetota include the Corynebacterium , Mycobacterium , Nocardia and Streptomyces genera. The (low G + C) Bacillota, have a 45–60% GC content, but this is lower than that of the Actinomycetota. Although bacteria are traditionally divided into two main groups, gram-positive and gram-negative, based on their Gram stain retention property, this classification system

2052-401: The marked differences in the ultrastructure and chemical composition of the bacterial cell wall, marked by the absence or presence of an outer lipid membrane. All gram-positive bacteria are bounded by a single-unit lipid membrane, and, in general, they contain a thick layer (20–80 nm) of peptidoglycan responsible for retaining the Gram stain. A number of other bacteria—that are bounded by

2106-411: The nuclei of adherent cells. In this application, crystal violet works as an intercalating dye and allows the quantification of DNA which is proportional to the number of cells. The dye is used as a histological stain , particularly in Gram staining for classifying bacteria . In forensics , crystal violet was used to develop fingerprints . Crystal violet is also used as a tissue stain in

2160-526: The outer cell membrane in gram-negative bacteria (diderms) has evolved as a protective mechanism against antibiotic selection pressure. Some bacteria, such as Deinococcus , which stain gram-positive due to the presence of a thick peptidoglycan layer and also possess an outer cell membrane are suggested as intermediates in the transition between monoderm (gram-positive) and diderm (gram-negative) bacteria. The diderm bacteria can also be further differentiated between simple diderms lacking lipopolysaccharide,

2214-437: The peptidoglycan. Along with cell shape , Gram staining is a rapid method used to differentiate bacterial species. Such staining, together with growth requirement and antibiotic susceptibility testing, and other macroscopic and physiologic tests, forms a basis for practical classification and subdivision of the bacteria (e.g., see figure and pre-1990 versions of Bergey's Manual of Systematic Bacteriology ). Historically ,

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2268-411: The positive charges on the nitrogen atoms lead to an enhancement of the electrophilic character of the central carbon, which allows the nucleophilic attack by water molecules. This effect produces a slight fading of the yellow colour. Crystal violet is used as a textile and paper dye, and is a component of navy blue and black inks for printing, ball-point pens, and inkjet printers. Historically, it

2322-414: The preparation of light microscopy sections. In laboratory, solutions containing crystal violet and formalin are often used to simultaneously fix and stain cells grown in tissue culture to preserve them and make them easily visible, since most cells are colourless. It is also sometimes used as a cheap way to put identification markings on laboratory mice ; since many strains of lab mice are albino ,

2376-747: The products. The FDA report states: "Like MG ( malachite green ), CV (crystal violet) is readily absorbed into fish tissue from water exposure and is reduced metabolically by fish to the leuco moiety, leucocrystal violet (LCV). Several studies by the National Toxicology Program reported the carcinogenic and mutagenic effects of crystal violet in rodents. The leuco form induces renal, hepatic and lung tumor in mice." In 2019, Health Canada found medical devices that use gentian violet to be safe for use but recommended to stop using all drug products that contain gentian violet, including on animals, causing Canadian engineering schools to revisit

2430-463: The purple colour stays on their fur for several weeks. Crystal violet can be used as an alternative to Coomassie brilliant blue (CBB) in staining of proteins separated by SDS-PAGE , reportedly showing a 5x improved sensitivity vs CBB. Gentian violet has antibacterial , antifungal , antihelminthic , antitrypanosomal , antiangiogenic , and antitumor properties. It is used medically for these properties, in particular for dentistry , and

2484-415: The reaction of dimethylaniline with phosgene to give 4,4′-bis(dimethylamino) benzophenone ( Michler's ketone ) as an intermediate. This was then reacted with additional dimethylaniline in the presence of phosphorus oxychloride and hydrochloric acid . The dye can also be prepared by the condensation of formaldehyde and dimethylaniline to give a leuco dye : Second, this colourless compound

2538-401: The solution, leaving only one of the nitrogen atoms positive charged. The p K a for the loss of the two protons are approximately 1.15 and 1.8. In alkaline solutions, nucleophilic hydroxyl ions attack the electrophilic central carbon to produce the colourless triphenylmethanol or carbinol form of the dye. Some triphenylmethanol is also formed under very acidic conditions when

2592-452: The surname of Hans Christian Gram ; as eponymous adjectives , their initial letter can be either capital G or lower-case g , depending on which style guide (e.g., that of the CDC ), if any, governs the document being written. Crystal violet 1.0 g/kg (oral, rats) Crystal violet or gentian violet , also known as methyl violet 10B or hexamethyl pararosaniline chloride ,

2646-502: The symptoms of MRSA ST398 can be employed. And until more information about antimicrobial susceptibilities are known, the ST398 strain should be treated as MRSA is.  Gram-positive In bacteriology , gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall . The Gram stain

2700-458: The world. The primary method of transmission of MRSA ST398 is through contact with infected animals, which classifies it as a zoonotic agent. People who work with livestock or live in close proximity to them are the most vulnerable to the infection. In healthcare settings, people with open wounds are most susceptible to the infection. Therefore, to prevent transmission, wounds should stay covered and infected patients should not be near each other. As

2754-628: Was first synthesized in 1883 by Alfred Kern (1850–1893) working in Basel at the firm of Bindschedler and Busch. To optimize the difficult synthesis which used the highly toxic phosgene , Kern entered into a collaboration with the German chemist Heinrich Caro at BASF . Kern also found that by starting with diethylaniline rather than dimethylaniline , he could synthesize the closely related violet dye now known as C.I. 42600 or C.I. Basic violet 4. The name "gentian violet" (or Gentianaviolett in German)

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2808-468: Was found specifically in people who were frequently in contact with livestock, particularly pigs and veal calves. A study from a Dutch farm found that most of the MRSA strains found in livestock and humans were of the CC398 isolate. The study also found that the closer people lived to a livestock farm, the more cases of MRSA ST398 were found. Since then, the strain has also been detected in many other regions of

2862-432: Was originally used for a mixture of methyl pararosaniline dyes ( methyl violet ), but is now often considered a synonym for crystal violet . The name refers to its colour, being like that of the petals of certain gentian flowers; it is not made from gentians or violets . A number of possible routes can be used to prepare crystal violet. The original procedure developed by the German chemists Kern and Caro involved

2916-433: Was the most common dye used in early duplication machines, such as the mimeograph and the ditto machine . It is sometimes used to colourize diverse products such as fertilizer , antifreeze , detergent , and leather . Marking blue , used to mark out pieces in metalworking , is composed of methylated spirits , shellac , and gentian violet. When conducting DNA gel electrophoresis , crystal violet can be used as

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