Actinobacillus | |
---|---|
Actinobacillus suis | |
Scientific classification | |
Domain: | Bacteria |
Phylum: | Pseudomonadota |
Class: | Gammaproteobacteria |
Order: | Pasteurellales |
Family: | Pasteurellaceae |
Genus: | Actinobacillus Brumpt 1910 |
Species | |
A. actinomycetemcomitans |
Actinobacillus is a genus of Gram-negative, nonmotile and non-spore-forming, oval to rod-shaped bacteria occurring as parasites or pathogens in mammals, birds, and reptiles. [1] It is a member of the family Pasteurellaceae. [2] The bacteria are facultatively anaerobic or aerobic, capable of fermenting carbohydrates (without production of gas), and of reducing nitrates. The genomic DNA contains between 40 and 47 mol % guanine plus cytosine.
Actinobacillus ( Pasteurella ) ureae and A. hominis occur in the respiratory tracts of healthy humans and may be involved in the pathogenesis of sinusitis, bronchopneumonia, and meningitis. A. actinomycetemcomitans occurs in the human oral microflora, [3] and together with anaerobic or capnophilic organisms (HACEK group organisms) may cause endocarditis. Actinobacilli are susceptible to most antibiotics of the beta-lactam family, aminoglycosides, tetracyclines, chloramphenicol, and many other antibacterial chemotherapeutics.
An analysis of A. actinomycetemcomitans indicated it was monophyletic with Haemophilus aphrophilus and H. segnis, and they were proposed to be reclassified as a new genus, Aggregatibacter (from the Latin aggregare, meaning "to come together"). [4] [5]
Helicobacter is a genus of gram-negative bacteria possessing a characteristic helical shape. They were initially considered to be members of the genus Campylobacter, but in 1989, Goodwin et al. published sufficient reasons to justify the new genus name Helicobacter. The genus Helicobacter contains about 35 species.
The HACEK organisms are a group of fastidious Gram-negative bacteria that are an unusual cause of infective endocarditis, which is an inflammation of the heart due to bacterial infection. HACEK is an abbreviation of the initials of the genera of this group of bacteria: Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella. The HACEK organisms are a normal part of the human microbiota, living in the oral-pharyngeal region.
Haemophilus influenzae is a Gram-negative, non-motile, coccobacillary, facultatively anaerobic, capnophilic pathogenic bacterium of the family Pasteurellaceae. The bacteria are mesophilic and grow best at temperatures between 35 and 37 °C.
Actinomyces is a genus of the Actinomycetia class of bacteria. They all are gram-positive. Actinomyces species are facultatively anaerobic and they grow best under anaerobic conditions. Actinomyces species may form endospores, and while individual bacteria are rod-shaped, Actinomyces colonies form fungus-like branched networks of hyphae. The aspect of these colonies initially led to the incorrect assumption that the organism was a fungus and to the name Actinomyces, "ray fungus".
The Pseudomonadales are an order of Pseudomonadota. A few members are pathogens, such as species of Pseudomonas, Moraxella, and Acinetobacter, which may cause disease in humans, animals and plants.
The Pasteurellaceae comprise a large family of Gram-negative bacteria. Most members live as commensals on mucosal surfaces of birds and mammals, especially in the upper respiratory tract. Pasteurellaceae are typically rod-shaped, and are a notable group of facultative anaerobes. Their biochemical characteristics can be distinguished from the related Enterobacteriaceae by the presence of oxidase, and from most other similar bacteria by the absence of flagella.
Haemophilus is a genus of Gram-negative, pleomorphic, coccobacilli bacteria belonging to the family Pasteurellaceae. While Haemophilus bacteria are typically small coccobacilli, they are categorized as pleomorphic bacteria because of the wide range of shapes they occasionally assume. These organisms inhabit the mucous membranes of the upper respiratory tract, mouth, vagina, and intestinal tract. The genus includes commensal organisms along with some significant pathogenic species such as H. influenzae—a cause of sepsis and bacterial meningitis in young children—and H. ducreyi, the causative agent of chancroid. All members are either aerobic or facultatively anaerobic. This genus has been found to be part of the salivary microbiome.
Pasteurella is a genus of Gram-negative, facultatively anaerobic bacteria. Pasteurella species are nonmotile and pleomorphic, and often exhibit bipolar staining. Most species are catalase- and oxidase-positive. The genus is named after the French chemist and microbiologist, Louis Pasteur, who first identified the bacteria now known as Pasteurella multocida as the agent of chicken cholera.
Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical (cocci) bacteria that share common metabolic and physiological characteristics. These bacteria, usually found in decomposing plants and milk products, produce lactic acid as the major metabolic end product of carbohydrate fermentation, giving them the common name lactic acid bacteria (LAB).
Food microbiology is the study of the microorganisms that inhabit, create, or contaminate food. This includes the study of microorganisms causing food spoilage; pathogens that may cause disease ; microbes used to produce fermented foods such as cheese, yogurt, bread, beer, and wine; and microbes with other useful roles, such as producing probiotics.
Aggregatibacter actinomycetemcomitans is a Gram-negative, facultative anaerobe, nonmotile bacterium that is often found in association with localized aggressive periodontitis, a severe infection of the periodontium. It is also suspected to be involved in chronic periodontitis. Less frequently, A. actinomycetemcomitans is associated with nonoral infections such as endocarditis. Its role in aggressive periodontitis was first discovered by Danish-born periodontist Jørgen Slots, a professor of dentistry and microbiology at the University of Southern California School of Dentistry.
Microbial biodegradation is the use of bioremediation and biotransformation methods to harness the naturally occurring ability of microbial xenobiotic metabolism to degrade, transform or accumulate environmental pollutants, including hydrocarbons, polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), heterocyclic compounds, pharmaceutical substances, radionuclides and metals.
Microbiology is the scientific study of microorganisms, those being of unicellular (single-celled), multicellular, or acellular. Microbiology encompasses numerous sub-disciplines including virology, bacteriology, protistology, mycology, immunology, and parasitology.
Aggregatibacter is a genus in the phylum Pseudomonadota (Bacteria), which contains three species, namely:
Aggregatibacter aphrophilus is a species of bacteria. It is one of the HACEK organisms.
Haemophilus pittmaniae is a Gram-negative species of bacterium of the family Pasteurellaceae. Strains of this species were originally isolated from humans. The species may be associated with respiratory infections in individuals with lung disease.
Four non-coding small RNAs containing a Fur box-like sequence were identified by bioinformatics analysis in Aggregatibacter actinomycetemcomitansHK1651 called JA01-JA04. The transcription of sRNAs was confirmed by Northern blot. Fur binding was demonstrated to each sRNA promoter, and that transcription of the sRNAs was decreased in presence of iron and increased by iron limitation. JA03 may have the ability to regulate biofilm formation. JA01 is conserved only among A. actinomycetemcomitans. JA02 is present in both A. actinomycetemcomitans and P. multocida. JA 03 and JA04 are most widely conserved and have orthologues across many Pasteurellaceae. HrrF RNA is another Fur-regulated sRNA conserved among the Pasteurcellaceae.
Jørgen Slots is a Danish-born periodontist notable for his contributions to the field of periodontology. He is currently professor of periodontology and microbiology at the Herman Ostrow School of Dentistry of USC, and served as chairman of periodontology from 1991 to 2001.
N-glycosyltransferase is an enzyme in prokaryotes which transfers individual hexoses onto asparagine sidechains in substrate proteins, using a nucleotide-bound intermediary, within the cytoplasm. They are distinct from regular N-glycosylating enzymes, which are oligosaccharyltransferases that transfer pre-assembled oligosaccharides. Both enzyme families however target a shared amino acid sequence asparagine—-any amino acid except proline—serine or threonine (N–x–S/T), with some variations.
Aggregatibacter segnis is a species of bacteria. A. segnis can be cultured on chocolate agar.