Bacteria
Yersinia enterocolitica
Yersinia enterocolitica is a species of gram-negative coccobacillus-shaped bacterium, belonging to the family Enterobacteriaceae. Infection from Yersinia enterocolitica causes the zoonotic disease yersiniosis. Most infected animals recover from the dis...
Wolbachia
Wolbachia is a genus of bacteria which infects arthropod species, including a high proportion of insects (~60% of species). It is one of the world's most common parasitic microbes and possibly the most common reproductive parasite in biosphere. Studies...
Vibrio vulnificus
Vibrio vulnificus is a species of Gram-negative, motile, curved, rod-shaped bacteria of the Vibrio Genus. Hollis et al. first reported it in 1976. It was given the name Beneckea vulnifica by Reichelt et al. in 1976 and in 1979 Vibrio vulnificus by Farm...
Vibrio parahaemolyticus
Vibrio parahaemolyticus is a curved, rod-shaped, Gram-negative bacterium found in brackish saltwater, which, when ingested, causes gastrointestinal illness in humans. V. parahaemolyticus is oxidase positive, facultatively aerobic, and does not form spo...
Vibrio cholerae
Vibrio cholerae is a gram negative comma-shaped bacterium with a polar flagellum that causes cholera in humans. V. cholerae belongs to the gamma subdivision of the Proteobacteria. Classical and El Tor are the two types of V. Cholerae identified by hema...
Treponema pallidum
Treponema pallidum is a species of spirochaete bacterium with subspecies that cause treponemal diseases such as syphilis, bejel, pinta and yaws. Since the organism has a waxy coat around it won't accept the gram stain. The Dieterle stain is used to det...
Streptococcus salivarius
Streptococcus salivarius is a species of spherical, Gram-positive bacteria which colonize the mouth and upper respiratory tract of humans a few hours after birth, making further exposure to the bacteria harmless. The bacterium is an opportunistic patho...
Streptococcus pyogenes
Streptococcus pyogenes is a spherical, Gram-positive bacterium is the cause of Group A streptococcal infections. It displays streptococcal group A antigen on its cell wall. When it is cultured on blood agar plates it produces large zones of beta-hemoly...
Streptococcus pneumoniae
Streptococcus pneumoniae, or pneumococcus, is Gram-positive, alpha-hemolytic, bile-soluble aerotolerant, anaerobic member of the genus Streptococcus. It was recognized as a major cause of pneumonia in the late 19th century and is thus the subject of ma...
Streptococcus oralis
Streptococcus oralis is a Gram positive bacterium that grows characteristically in chains. On a Wilkins-Chalgren agar plate it will form slam white colonies. It is classified as a member of the streptococcus mitis group and is found in high numbers in ...
Streptococcus mutans
Streptococcus mutans is a Gram-positive cocci, Facultative anaerobic bacterium commonly found in the human oral cavity and is a significant contributor to tooth decay. J Kilian Clarke first described the microbe in 1924. The first colonizers of the...
Enterococcus
Enterococcus is a Gram-positive, commensal bacterium inhabiting the gastrointestinal tracts of humans and other mammals. It is a main constituent of some probiotic food supplements. E. faecalis can cause life-threatening infections in humans, especiall...
Staphylococcus epidermidis
Staphylococcus epidermidis is one of thirty-three known species belonging to the genus Staphylococcus. It is part of our skin flora and can also be found in the mucous membranes and in animals. It is the most common species found in laboratory test due...
Staphylococcus aureus
Staphylococcus aureus is a facultative anaerobic gram-positive coccus, and is the most common cause of staph infections. It is commonly part of the skin flora found in the nose and on skin. Around 20% of the human population is long-term carriers. It g...
Serratia marcescens
Serratia marcescens is a species of Gram-negative, rod-shaped bacterium in the family Enterobacteriaceae. S. marcescens is involved in nosocomial infections particularly catheter-associated bacteremia. It is commonly found in respiratory and urinarty t...
Salmonella enterica
Salmonella enterica is a subspecies of Salmonella enterica, the rod shaped, flagellated, aerobic, Gram-negative bacterium. It is a member of the genus Salmonella and many of the pathogenic serovars of the S. enterica species are in this subspecies. ...
Rickettsia rickettsii
Rickettsia rickettsii is a gram-negative bacterium native to the New World and causes the malady known as Rocky Mountain spotted fever (RMSF). It is transmitted through the bit of an infected tick when it feeds on animals and humans. Humans are not nec...
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals and humans. It can be found in soil, water, skin flora, and most man-made environments throughout the world. It thrives in normal or hypoxic atmospheres; due to this it has ...
Neisseria meningitidis
Neisseria meningitidis is a heterotrophic gram-negative diplococcal bacterium best known for its role in meningitis and other forms of meningococcal disease such as meningococcemia. It is a major cause of morbidity and mortality during childhood in ind...
Mycoplasma genitalium
Mycoplasma genitalium is a small parasitic bacterium that lives on the ciliated epithelial cells of the primate genital and respiratory tracts. It is the smallest known free-living bacterium. Up until 2002 it was also considered to be the organism with...
Mycobacterium tuberculosis
Mycobacterium tuberculosis (MTB) is a pathogenic bacterial species in the genus Mycobacterium and the causative agent of most cases of tuberculosis. Robert Koch first discovered it in 1882 and that it had an unusual, waxy coating on the cell surface wh...
Mycobacterium smegmatis
Mycobacterium smegmatis is 3.0 to 5.0 µm long with a bacillus shape, an acid-fast bacterial species in the phylum Actinobacteria. It can be stained by Ziehl-Neelsen method and the auramine-rhodamine fluorescent method. It was first reported in 1884....
Mycobacterium leprae
Mycobacterium leprae, mostly found in warm tropical countries, is a bacterium that causes leprosy (Hansen's disease). It is an intracellular, pleomorphic, acid-fast bacterium. M. leprae is an aerobic rod-shaped surrounded by the characteristic waxy c...
Mycobacterium bovis
Mycobacterium bovis is a slow-growing, aerobic bacterium and the causative agent of tuberculosis in cattle. Similar to M. tuberculosis, M. bovis can jump the species barrier and cause tuberculosis in humans. It is estimated that M. bovis was respon...
Lactobacillus casei
Lactobacillus casei is a species of genus Lactobacillus found in the human intestine and mouth. Since it produces lactic acid it helps with the propagation of desirable bacteria. This species is documented to have a wide pH and temperature range. It al...
Klebsiella pneumoniae
Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose fermenting, facultative anaerobic, rod shaped bacterium found in the normal flora of the mouth, skin, and intestines. It is the most important member of the Klebsiella genus of...
Helicobacter pylori
Helicobacter pylori is a Gram-negative, microaerophilic bacterium that can inhabit various areas of the stomach, particularly the antrum. It causes low-level inflammation of the stomach lining and is linked to gastric ulcers and stomach cancer. Out of ...
Haemophilus influenzae
Haemophilus influenzae is a Gram-negative, rod-shaped bacterium first described in 1892 by Richard Pfeiffer during an influenza pandemic. It is generally aerobic but can grow as a facultative anaerobe. H. influenzae was mistakenly considered to be the ...
Haemophilus ducreyi
Haemophilus ducreyi is a fastidious gram-negative coccobacillus causing the sexually transmitted disease chancroid, a major cause of genital ulceration in developing countries characterized by painful sores on the genitalia. Early symptoms are dark...
Gardnerella
Gardnerella is a genus of gram-variable-staining facultative anaerobic bacteria of which G. vaginalis is the only species. It grows as small, circular, convex, gray colonies on chocolate agar. Colistin-oxolinic acid blood agar is a selective medium for...
Francisella tularensis
Francisella tularensis is a pathogenic species of gram-negative bacteria and the causative agent of tularemia or rabbit fever. It is a facultative intracellular bacterium. It is classified as a Class A agent by the U.S. government due to its ease of sp...
Escherichia coli
Escherichia coli is a Gram-negative rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms. Most strains are harmless; however, some such as O157:H7 can cause food poisoning in humans and are often responsible for ...
Enterococcus faecalis
Enterococcus faecalis "“ formerly classified as part of the Group D Streptococcus system "“ is a Gram-positive, commensal bacterium inhabiting the gastrointestinal tracts of humans and other mammals. It is one of the main constituents of some probi...
Corynebacterium diphtheriae
Corynebacterium diphtheriae is a pathogenic bacterium that causes diphtheria. It was discovered in 1884. There are four subspecies C. diphtheriae mitis, C. diphtheriae intermedius, C. diphtheriae gravis, and C. diphtheriae belfanti. They all are a litt...
Clostridium tetani
Clostridium tetani is a rod-shaped, anaerobic bacterium of the genus Clostridium. It's a gram-positive and resembles tennis rackets or drumsticks on a gram stain. It can be found as spores in soil and the gastrointestinal tract of animals. It produces ...
Clostridium perfringens
Clostridium perfringens (formerly known as C. welchii) is a Gram-positive, rod-shaped, anaerobic, spore-forming bacterium of the genus Clostridium. It is always present in nature and is a normal component of decaying vegetation, marine sediment, the in...
Clostridium difficile
Clostridium difficile, also known as "CDF/cdf", or "C. diff", is a Gram-positive bacteria of the genus Clostridium that causes severe diarrhea and other intestinal disease when competing bacteria in the gut flora are wiped out by antibiotics. They are ...
Clostridium botulinum
Clostridium botulinum is a gram-positive, rod-shaped bacterium that produces neurotoxins, known as botulinum neurotoxins types A-G, that cause the flaccid muscular paralysis seen in botulism. It is the main paralytic agent in botox and is commonly foun...
Campylobacter jejuni
Campylobacter jejuni is a species of curved, helical shaped, non-spore forming, Gram-negative microaerophilic, bacteria commonly found in animal feces. It is one of the most common causes of human gastroenteritis in the world. This food poisoning can b...
Campylobacter fetus
Campylobacter fetus is a species of Gram-negative, motile bacteria with characteristic "S-shaped" rod morphology similar to members of the genus Vibrio. It is oxidase-positive like other members of the Campylobacter genus. C. fetus can cause aborti...
Burkholderia pseudomallei
Burkholderia pseudomallei is a Gram-negative, bipolar, aerobic, motile rod-shaped bacterium. It causes the disease melioidosis in humans and animals and is also capable of infecting plants. The bacteria can from in a number of artificial environments. ...
Burkholderia mallei
Burkholderia mallei is a gram-negative bipolar aerobic bacterium. The human and animal pathogen causes Glanders. The Latin name of this disease gave name to the causative agent species. It is related to B. pseudomallei although the bacterium is nonmoti...
Burkholderia cepacia complex
Burkholderia cepacia complex (BCC), is a group of catalase-producing, non-lactose-fermenting Gram-negative bacteria composed of at least nine different species. It is an important human pathogen that often causes pneumonia in immunocompromised individu...
Bordetella pertussis
Bordetella pertussis is a Gram-negative, aerobic coccobacillus of the genus Bordetella. It is the causative agent of pertussis or whooping cough and it is non-motile. There is no zoonotic reservoir thus humans are the only hosts. Bacterium is spread ...
Bordetella bronchiseptica
Bordetella bronchiseptica is a small, gram-negative, rod-shaped bacterium of the genus Bordetella. It can cause bronchitis although it rarely infects humans. It is closely related to pertussis which causes whooping cough and B. bronchiseptica can persi...
Bartonella henselae
Bartonella henselae is a proteobacterium that can cause bacteremia, endocarditis, bacillary angiomatosis, and peliosis hepatis. It is a causative agent of cat-scratch disease which occurs after a cat bite or scratch. The disease is characterized by swe...
Bacillus subtilis
Bacillus subtilis, also known as hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium commonly found in soil. It is rod-shaped and a member of the genus Bacillus. It also has the ability to form a tough, protective endospore,...
Bacillus cereus
Bacillus cereus is an endemic, soil-dwelling, Gram-positive, rod-shaped, beta hemolytic bacterium. Some are harmful to humans while other strains are beneficial as probiotics for animals. They are aerobes and can produce protective endospores. B. c...
Bacillus anthracis
Bacillus anthracis is a Gram-positive spore-forming, rod-shaped bacterium, with a width of 1-1.2µm and a length of 3-5µm. It can grow in aerobic or anaerobic conditions. It is the only known bacterium to synthesize a protein capsule and the only ...
Agrobacterium tumefaciens
Agrobacterium tumefaciens is the causal agent of crown gall disease (the formation of tumours) in over 140 species of dicot. It is rod shaped. Symptoms are caused by the insertion of a small segment of DNA into the plant cell. It is an alphaproteobacte...
Acinetobacter baumannii
Acinetobacter baumannii is a species of pathogenic bacteria that is resistant to most antibiotics. Some think the disease is killing tens of thousands of U.S. hospital patients each year due to its resistance to drug treatment. It can cause severe pneu...