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 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 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) 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. History The genus 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 the basis of molecular signatures that are uniquely found for each genus. Taxonomy 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 the Burkholderia cepacia complex, another clade comprises B. pseudomallei and closely related species, and the last clade encompasses