46-533: See text Burkholderia is a genus of Pseudomonadota whose pathogenic members include the Burkholderia cepacia complex , which attacks humans and Burkholderia mallei , responsible for glanders , a disease that occurs mostly in horses and related animals; Burkholderia pseudomallei , causative agent of melioidosis ; and Burkholderia cepacia , an important pathogen of pulmonary infections in people with cystic fibrosis (CF). Burkholderia species
92-415: A correlation of microbial composition in children with and without nonalcoholic fatty liver disease (NAFLD), wherein patients with NAFLD have a higher abundance of Gammaproteobacteria than patients without the disease. Classes Betaproteobacteria and Gammaproteobacteria are prevalent within the human oral cavity, and are markers for good oral health. The oral microbiome consists of 11 habitats, including
138-503: A diverse group. Though some species may stain Gram-positive or Gram-variable in the laboratory, they are nominally Gram-negative . Their unique outer membrane is mainly composed of lipopolysaccharides , which helps differentiate them from the Gram-positive species. Most Pseudomonadota are motile and move using flagella. Many move about using flagella , but some are nonmotile, or rely on bacterial gliding . Pseudomonadota have
184-690: A proposal for its reclassification into distinct phyla: Desulfobacterota (encompassing Thermodesulfobacteria ), Myxococcota , and Bdellovibrionota (comprising Oligoflexia ). The class Epsilonproteobacteria was additionally identified within the Pseudomonadota phylum. This class is characterized by its significance as chemolithotrophic primary producers and its metabolic prowess in deep-sea hydrothermal vent ecosystems. Noteworthy pathogenic genera within this class include Campylobacter , Helicobacter , and Arcobacter . Analysis of phylogenetic tree topology and genetic markers revealed
230-480: A range of topics and characteristics including metabolomic response to antibiotics, contact-dependent interactions between bacterial communities, and genomic potential to yield beneficial products. In Burkholderia species, certain antibiotics such as trimethoprim has been shown to induce and upregulate a large amount of the metabolome , inducing over 100 silent secondary metabolite gene clusters in Burkholderia thailandensis . These global activators can be used as
276-430: A reaction similar to disulfiram when alcohol is consumed after it is used, in particular when used in combination with sulfamethoxazole . Based on the studies that show that trimethoprim crosses the placenta and can affect folate metabolism, there has been growing evidence of the risk of structural birth defects associated with trimethoprim, especially during the first trimester of pregnancy. The trophoblasts in
322-426: A relevant signature of disease in the human gastrointestinal (GI) tract, by operating as a marker for microbiota instability. The human gut microbiome consists mainly of four phyla: Firmicutes , Bacteroidetes , Actinobacteria , and Pseudomonadota. Microorganism gut colonization is dynamic from birth to death, with stabilization at the first few years of life, to higher diversity in adults, to reduced diversity in
368-486: A significant role in bacterial self recognition and community formation. Burkholderia species have been shown to be a potential source of beneficial products such as antimicrobials and biosurfactants . Along with the related genus Pseudomonas , Burkholderia can synthesize a particular class of biosurfactant called rhamnolipids . Rhamnolipids synthesized by Burkholderia have differing chemical characteristics (compared to those synthesized by Pseudomonas ) and thus have
414-468: A significant role in mediating cell to cell communication specifically in B. thailandensis . In this interaction, cells release protein toxins to the surrounding environment, and only those with a corresponding protective protein (usually bacteria of the same strain) will not have its growth inhibited or die. Furthermore, recipient cells that have the corresponding protein then undergo changes to gene expression and phenotype that promotes community formation in
460-564: A source of investigation into how the metabolomes of pathogenic bacterial species respond to antibiotic stress and how bacterial species can vary in response to them. It has been shown that closely related cystic fibrosis -associated Burkholderia species respond to trimethoprim with differing levels of expression of various secondary metabolites , highlighting the personalized nature of metabolomics in related bacterial strains. Research focused on interbacterial signaling using Burkholderia has shown that contact-dependent growth inhibition plays
506-615: A symbiotic relationship with plant roots, incorporating Pseudomonadota into agricultural practices aligns with principles of sustainable farming . These bacteria contribute to soil health and fertility, promote natural pest management, and enhance the resilience of crops to environmental stressors. Trimethoprim Trimethoprim ( TMP ) is an antibiotic used mainly in the treatment of bladder infections . Other uses include for middle ear infections and travelers' diarrhea . With sulfamethoxazole or dapsone it may be used for Pneumocystis pneumonia in people with HIV/AIDS . It
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#1732765671054552-427: A variety of compounds. Bioleaching , done by various Thiobacillus species, are a primary example of this. Any iron and sulfur oxidizing species has the potential to uncover metals and low-grade ores that conventional mining techniques were unable to extract. At present, they are most often used for recovering copper and uranium, but researchers are looking to expand this field in the future. The downside of this method
598-475: A well-known pathogenic genus, Pseudomonas is also capable of biodegradation of certain materials, like cellulose. The Hydrogenophilalia are thermophilic chemoheterotrophs and autotrophs. The bacteria typically use hydrogen gas as an electron donor, but can also use reduced sulfuric compounds. Because of this ability, scientists have begun to use certain species of Hydrogenophilalia to remove sulfides that contaminate industrial wastewater systems. The type order
644-431: A wide variety of metabolism types. Most are facultative or obligate anaerobes , chemolithoautotrophs , and heterotrophs , though numerous exceptions exist. A variety of distantly related genera within the Pseudomonadota obtain their energy from light through conventional photosynthesis or anoxygenic photosynthesis . The Acidithiobacillia contain only sulfur, iron, and uranium-oxidizing autotrophs . The type order
690-554: Is also found in marine environments. S.I. Paul et al. (2021) isolated and characterized Burkholderia cepacia from marine sponges of the Saint Martin's Island of the Bay of Bengal , Bangladesh . The Burkholderia (previously part of Pseudomonas ) genus name refers to a group of virtually ubiquitous Gram-negative , obligately aerobic , rod-shaped bacteria that are motile by means of single or multiple polar flagella , with
736-498: Is present in the atmosphere, they are able to compete with the abiotic iron(II) oxidation that is already occurring in the environment. The only confirmed type order for this class is the Mariprofundaceae , which does not contain any known pathogenic species. Transformation , a process in which genetic material passes from one bacterium to another, has been reported in at least 30 species of Pseudomonadota distributed in
782-518: Is renowned for being catalase positive (affecting patients with chronic granulomatous disease ) and its ability to degrade chlororganic pesticides and polychlorinated biphenyls . The conserved RNA structure anti-hemB RNA motif is found in all known bacteria in this genus. Due to their antibiotic resistance and the high mortality rate from their associated diseases, B. mallei and B. pseudomallei are considered to be potential biological warfare agents, targeting livestock and humans. The genus
828-419: Is sixty thousand times greater than for human dihydrofolate reductase. Sulfamethoxazole inhibits dihydropteroate synthase , an enzyme involved further upstream in the same pathway. Trimethoprim and sulfamethoxazole are commonly used in combination due to possible synergistic effects, and reduced development of resistance. This benefit has been questioned. Trimethoprim was first used in 1962. In 1972, it
874-522: Is taken orally (swallowed by mouth). Common side effects include nausea, changes in taste, and rash. Rarely it may result in blood problems such as not enough platelets or white blood cells . Trimethoprim may cause sun sensitivity. There is evidence of potential harm during pregnancy in some animals but not humans. It works by blocking folate metabolism via dihydrofolate reductase in some bacteria, preventing creation of bacterial DNA and RNA and leading to bacterial cell death. Trimethoprim
920-730: Is that the bacteria produce acidic byproducts that end up in acid mine drainage . Bioleaching has significant economic promise if it can be controlled and not cause any further harm to the environment. Pseudomonadota are microbes commonly found within soil systems. Microbes play a crucial role in the surrounding ecosystem by performing functions such as nutrient cycling , carbon dioxide fixation, decomposition , and nitrogen fixation. Pseudomonadota can be described as phototrophs , heterotrophs , and lithotrophs . As heterotrophs (examples Pseudomonas and Xanthomonas ) these bacteria are effective in breaking down organic matter, contributing to nutrient cycling. Additionally, photolithotrophs within
966-714: Is the Acidithiobacillaceae , which includes five different Acidithiobacillus species used in the mining industry. In particular, these microbes assist with the process of bioleaching , which involves microbes assisting in metal extraction from mining waste that typically extraction methods cannot remove. Some Alphaproteobacteria can grow at very low levels of nutrients and have unusual morphology within their life cycles. Some form stalks to help with colonization, and form buds during cell division. Others include agriculturally important bacteria capable of inducing nitrogen fixation in symbiosis with plants. The type order
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#17327656710541012-647: Is the Caulobacterales , comprising stalk-forming bacteria such as Caulobacter . The mitochondria of eukaryotes are thought to be descendants of an alphaproteobacterium. The Betaproteobacteria are highly metabolically diverse and contain chemolithoautotrophs , photoautotrophs , and generalist heterotrophs . The type order is the Burkholderiales , comprising an enormous range of metabolic diversity, including opportunistic pathogens . These pathogens are primary for both humans and animals, such as
1058-550: Is the Hydrogenophilaceae which contains the genera Thiobacillus, Petrobacter, Sulfuricella, Hydrogenophilus and Tepidiphilus . Currently, no members of this class have been identified as pathogenic. The Zetaproteobacteria are the iron-oxidizing neutrophilic chemolithoautotrophs , distributed worldwide in estuaries and marine habitats. This group is so successful in its environment due to their microaerophilic nature. Because they require less oxygen than what
1104-521: The Burkholderia cepacia complex, another clade comprises B. pseudomallei and closely related species, and the last clade encompasses of most of the phytogenic species within the genus, including B. glumae and B. gladioli . Conserved signature indels are specific for each of these subgroups within the genus that aid in demarcating members of this extremely large and diverse genus. Recently, research in Burkholderia species has investigated
1150-420: The bacteria responsible for nitrogen fixation . Previously, the Pseudomonadota phylum included two additional classes, namely Deltaproteobacteria and Oligoflexia . However, further investigation into the phylogeny of these taxa through genomic marker analysis demonstrated their separation from the Pseudomonadota phylum. Deltaproteobacteria has been identified as a diverse taxonomic unit, leading to
1196-603: The "purple bacteria and their relatives". The group was later formally named the 'Proteobacteria' after the Greek god Proteus, who was known to assume many forms. In 2021 the International Committee on Systematics of Prokaryotes designated the synonym Pseudomonadota, and renamed many other prokaryotic phyla as well. This renaming of several prokaryote phyla in 2021, including Pseudomonadota, remains controversial among microbiologists, many of whom continue to use
1242-641: The basis of molecular signatures that are uniquely found for each genus. Burkholderia species form a monophyletic group within the Burkholderiales order of the Betaproteobacteria . Currently, the 48 validly named species can be distinguished from related genera (i.e. Paraburkholderia ) and all other bacteria by conserved signature indels in a variety of proteins. These indels represent exclusive common ancestry shared among all Burkholderia species. The genus has three distinct monophyletic clusters. One group consists of all species belonging to
1288-410: The classes alpha, beta, and gamma. The best-studied Pseudomonadota with respect to natural genetic transformation are the medically important human pathogens Neisseria gonorrhoeae (class beta), and Haemophilus influenzae (class gamma). Natural genetic transformation is a sexual process involving DNA transfer from one bacterial cell to another through the intervening medium and the integration of
1334-478: The direct divergence of Epsilonproteobacteria from the Pseudomonadota phylum. Limited outgroup data and low bootstrap values support these discoveries. Despite further investigations, consensus has not been reached regarding the monophyletic nature of Epsilonproteobacteria within Proteobacteria, prompting researchers to propose its taxonomic separation from the phylum. The proposed reclassification of
1380-436: The donor sequence into the recipient genome. In pathogenic Pseudomonadota, transformation appears to serve as a DNA repair process that protects the pathogen's DNA from attack by their host's phagocytic defenses that employ oxidative free radicals . Due to the distinctive nature of each of the six classes of Pseudomonadota, this phylum occupies a multitude of habitats. These include: Studies have suggested Pseudomonadota as
1426-463: The earlier name Proteobacteria, of long standing in the literature. The phylum Pseudomonadota encompasses classes Acidithiobacillia, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Hydrogenophilia , and Zetaproteobacteria. The phylum includes a wide variety of pathogenic genera, such as Escherichia , Salmonella , Vibrio , Yersinia , Legionella , and many others. Others are free-living (non- parasitic ) and include many of
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1472-524: The early fetus are sensitive to changes in the folate cycle. A 2013 study found a doubling in the risk of miscarriage in women exposed to trimethoprim in the early pregnancy. Trimethoprim binds to dihydrofolate reductase and inhibits the reduction of dihydrofolic acid (DHF) to tetrahydrofolic acid (THF). THF is an essential precursor in the thymidine synthesis pathway and interference with this pathway inhibits bacterial DNA synthesis. Trimethoprim's inhibitory activity for bacterial dihydrofolate reductase
1518-535: The elderly. The gut microbiome conducts processes like nutrient synthesis, chemical metabolism , and the formation of the gut barrier. Additionally, the gut microbiome facilitates host interactions with its surrounding environment through regulation of nutrient absorption and bacterial intake. In 16s rRNA and metagenome sequencing studies, Proteobacteria have been identified as bacteria that prompts endotoxemia (an inflammatory gut response) and metabolic disorders in human GI tracts. Another study by Michail et al. showed
1564-410: The exception of Burkholderia mallei , which is nonmotile. Members belonging to the genus do not produce sheaths or prosthecae and are able to use poly-beta-hydroxybutyrate (PHB) for growth. The genus includes both animal and plant pathogens , as well as some environmentally important species. In particular, B. xenovorans (previously named Pseudomonas cepacia then B. cepacia and B. fungorum )
1610-414: The form of biofilms . This occurs even if the recipient cell was not of the same bacterial strain which highlights the importance of this system. The genes that encode the protein toxins and the rest of the contact-dependent inhibition system can become mobile in the form of a transposon that can transfer between cells and is critical to communal aspect of the system. Thus, contact-dependent signaling plays
1656-502: The horse pathogen Burkholderia mallei , and Burkholderia cepacia which causes respiratory tract infections in people with cystic fibrosis. The Gammaproteobacteria are one of the largest classes in terms of genera, containing approximately 250 validly published names. The type order is the Pseudomonadales , which include the genera Pseudomonas and the nitrogen-fixing Azotobacter , along with many others. Besides being
1702-682: The name Epsilonproteobacteria is Epsilonbacteraeota , later revised to Campylobacterota in 2018. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LSPN) and the National Center for Biotechnology Information (NCBI). The group Pseudomonadota is defined based on ribosomal RNA (rRNA) sequencing, and are divided into several subclasses. These subclasses were regarded as such for many years, but are now treated as various classes of
1748-704: The oral cavity. Pseudomonadota bacteria have a symbiotic or mutualistic association with plant roots, an example being in the rhizomes of potato plants. Because of this symbiotic relationship, farmers have the ability to increase their crop yields. Healthier root systems can lead to better nutrient uptake, improved water retention, increased resistance to diseases and pests, and ultimately higher crop yields per acre. Increased agricultural output can spark economic growth, contribute to food security, and lead to job creation in rural areas. As briefly mentioned in previous sections, members of Pseudomonadota have vast metabolic abilities that allow them to utilize and produce
1794-857: The order Hydrogenophilales Pseudomonadota classes with validly published names include some prominent genera: e.g.: Alphaproteobacteria Zetaproteobacteria Gammaproteobacteria Betaproteobacteria Hydrogenophilalia Alphaproteobacteria " Mariprofundia " ( Zetaproteobacteria ) " Thiohalorhabdales " Methylothermaceae 2 Algiphilaceae Methylothermaceae Acidithiobacillia Gammaproteobacteria (nested Betaproteobacteria & Hydrogenophilalia ) " Caulobacteria " ( Alphaproteobacteria ) " Mariprofundia " ( Zetaproteobacteria ) " Magnetococcia " clade 1 "Foliamicales" clade 3 Immundisolibacterales clade 5 "Acidithiobacillidae" ( Acidithiobacillia ) "Neisseriidae" ( Betaproteobacteria & nested Hydrogenophilalia ) "Pseudomonadidae" ( Gammaproteobacteria ) Pseudomonadota are
1840-640: The phylum are able to perform photosynthesis using sulfide or elemental sulfur as electron donors , which enables them to participate in carbon fixation and oxygen production even in anaerobic conditions. These Pseudomonadota bacteria are also considered copiotrophic organisms, meaning they can be found in environments with high nutrient availability. These environments have ample sources of carbon and other nutrients, environments like fertile soils, compost, and sewage. These copiotrophic bacteria are able to enhance soil health by performing nutrient cycling and waste decomposition. Because this phylum are able to form
1886-485: The phylum. These classes are monophyletic . The genus Acidithiobacillus , part of the Gammaproteobacteria until it was transferred to class Acidithiobacillia in 2013, was previously regarded as paraphyletic to the Betaproteobacteria according to multigenome alignment studies . In 2017, the Betaproteobacteria was subject to major revisions and the class Hydrogenophilalia was created to contain
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1932-760: The potential for novel applications. List of species: Pseudomonadota Pseudomonadota (synonym Proteobacteria ) is a major phylum of Gram-negative bacteria . Currently, they are considered the predominant phylum within the realm of bacteria. They are naturally found as pathogenic and free-living (non- parasitic ) genera. The phylum comprises six classes Acidithiobacillia , Alphaproteobacteria , Betaproteobacteria , Gammaproteobacteria , Hydrogenophilia , and Zetaproteobacteria . The Pseudomonadota are widely diverse, with differences in morphology , metabolic processes, relevance to humans, and ecological influence. American microbiologist Carl Woese established this grouping in 1987, calling it informally
1978-407: The tongue dorsum, hard palate , tonsils, throat, saliva, and more. Changes in the oral microbiome are due to endogenous and exogenous factors like host lifestyle, genotype , environment, immune system, and socioeconomic status. Considering diet as a factor, high saturated fatty acid (SAF) content, achieved through poor diet, has been correlated to increased abundance of Betaproteobacteria in
2024-429: The treatment of anaerobic infections such as Clostridioides difficile colitis (the leading cause of antibiotic-induced diarrhea). Trimethoprim has been used in trials to treat retinitis . Resistance to trimethoprim is increasing, but it is still a first-line antibiotic in many countries. Cultures and susceptibility tests should be done to make sure bacteria are treated by trimethoprim. It may be involved in
2070-482: Was first used in 1962. It is on the World Health Organization's List of Essential Medicines . It is available as a generic medication. It is primarily used in the treatment of urinary tract infections , although it may be used against any susceptible aerobic bacterial species . It may also be used to treat and prevent Pneumocystis jirovecii pneumonia. It is generally not recommended for
2116-422: Was named after Walter H. Burkholder , plant pathologist at Cornell University . The first species placed in the genus were transfers from Pseudomonas , on the basis of various biochemical tests. Until recently, the genus Burkholderia was inclusive of all Paraburkholderia species. However, the genus Paraburkholderia is phylogenetically distinct, and can be distinguished from all Burkholderia species on
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