Bacteria

This is a Gram negative bacteria associated with fresh and aquatic environments. There are 14 species, some of which have been identified as potential human pathogens. One of the most notable species is A. hydrophila which has been linked to diseases in fish as well.

Occurs in soil and water. Occasional opportunistic pathogen of humans.

A novel species of the Genus Bacillus

Member of the Genus Bacillus. Used in commmercial insecticides for the control of crop-destroying and disease carrying insects

This organism is closely related to Bacteroides fragilis and is commonly isolated from feces and other clinical samples.

Members of the genus Brevibacterium are are tiny, gram-positive, coryneform bacilli. They test positive for Catalase and negative for Oxidase. Despite being generally considered skin flora, Brevibacterium casei is a known opportunistic pathogen. It is the most frequently isolated species in the genus and has been known to cause sepsis, especially in cases where a catheter is present.

A Gram negative non-fermenting rod isolated from the environment and clinical samples.

A gram negative rod associated with water environments. It has been known to cause septicemia, meningitis, and wound infections in humans.

Member of the Enterobacteriaceae family. It is found in the feces of humans and animals and can be an opportunistic pathogen. When present in the environment they are usually in the form of fecal contaminants.

Member of the Enterobacteriaceae family. It is found in the feces of humans and animals and can be an opportunistic pathogen.

This organism has been isolated from both water and hospital environments. It has been reported on clinical isolates.

Genus of Gram-positive irregular bacilli that can be isolated from the skin or mucous membranes of humans.

Widely distributed in nature, occuring in fresh water, soil, and sewage. Opportunistic pathogen of humans.

Members of the genus Enterobacter are gram-negative, lactose-fermenting bacilli. They are opportunistic pathogens once outside of their normal intestinal environment. Human infection generally follows the fecal-oral route, although other routes are also possible. Enterobacter is a leading cause of nosocomial infections, especially urinary tract infections and peritonitis. As fecal coliforms, their presence can indicate wastewater contamination.

Members of the genus Enterobacter are gram-negative, lactose-fermenting bacilli. They are opportunistic pathogens once outside of their normal intestinal environment. Human infection generally follows the fecal-oral route, although other routes are also possible. Enterobacter is a leading cause of nosocomial infections, especially urinary tract infections and peritonitis. As fecal coliforms, their presence can indicate wastewater contamination.

Members of the genus Enterobacter are gram-negative, lactose-fermenting bacilli. They are opportunistic pathogens once outside of their normal intestinal environment. Human infection generally follows the fecal-oral route, although other routes are also possible. Enterobacter is a leading cause of nosocomial infections, especially urinary tract infections and peritonitis. As fecal coliforms, their presence can indicate wastewater contamination.

This result indicates that gram-negative rods that ferment lactose were found on culture. This group contains a wide variety of genera including Citrobacter, Enterobacter, Escherichia, and Klebsiella. Many of these organisms cause a wide variety of diseases and infections, and several can be considered true pathogens.

Member of the Enterobacteriaceae family. It is found in the feces of humans and animals and can be an opportunistic pathogen.

Widely distributed in soil and water. Isolated from human clinical specimens. Clinical significance is uncertain. Previously designated as CDC group IIb. Includes strains designated Flav. indologenes and Flav. gleum. Yellow pigment often produced.

Widely distributed in soil and water, also found in raw meats, milk and other foods. Common in hospital environments and may cause nosocomial infections.

Widely distributed in soil and water, also found in raw meats, milk and other foods. Common in hospital environments and may cause nosocomial infections.

The genus Hydrogenophaga is a newly-created grouping of gram-negative bacteria that had been previously classified as species of the genus Pseudomonas. These organisms are chemolithotrophic, requiring only minimal minerals for growth. As such, they are commonly isolated from wastewater streams and other industrial water sources. They should be considered non-pathogenic.

Klebsiella species are Gram negative bacteria considered to be opportunistic pathogens. They have been isolated from the environment and in mammalian mucosal surfaces.

A species of Legionella that has been implicated in cases of Pontiac Fever and pneumonia. It is also a precurser for the potential growth of Legionella pneumophila because of environmental growth characteristics and similarities between the species.

L. pneumophila is the etiologic agent of Legionnaire's Disease, a type of pneumonia that was first widely recognized in 1976 following an outbreak in Philadelphia. Legionella pneumophila is a free-living, gram-negative bacilli that is generally motile, possessing from one to three polar flagella. It is ubiquitous in aquatic environments, but can be found outside of lakes and streams. Additionly, the bacteria can be found in cooling towers, air conditioners, spa equipment, fountains, humidifiers, and potable water systems. They grow in a range of temperatures from 5 to 63 degrees Celsius, with optimal growth in the range of 25 to 40 degrees. Legionella often forms a parasitic relationship with amoebae in its environment. The bacteria is able to resist destruction by the protozoan, and so is provided protection from a variety of biocidal treatments and other harsh environmental conditions. As the bacteria multiplies, it eventually kills the host cells and moves back into the environment. Humans become accidental hosts when contaminated water is inhaled, be it through exhaust from a cooling tower or the mist in a shower. There are at least 14 known serological groups of L. pneumophila, but serogroup 1 is the most prevalent and is considered to be the most pathological.

Methylobacterium dichloromethanicum is a species originally isolated from the soil at a treatment plant that dealt with halogenated hydrocarbons. The organism is pollution-resistant and is capable of digesting several different types of halo-organic compounds. It is not known to be pathogenic at this time.

Newly described genus consisting of yellow or orange pigmented motile rods previously designated as CDC A4 and A5. Pathogenic potential is uncertain. Rarely encountered in clinical specimens.

Members of the genus Micrococcus are generally considered skin flora, although they are opportunistic pathogens. They are gram-positive cocci that test Catalase-positive. It is easy to differentiate them from Staphylococcus species, however, as Micrococcus species form bright yellow colonies on tryptic soy agar supplemented with 5% sheep blood.

This genus of bacteria if part of the normal flora of the upper respiratory tract and urinary tract of humans and animals. It rarely causes disease in humans.

A Gram negative rod previously named Moraxella urethralis. Reported infections have been associated with urinary catheters.

Members of the genus Paenibacillus have recently been split off from the genus Bacillus and are motile, gram-positive rods. They can be easily distinguished on culture media due to their characterisitic growth patterns which form vortex-like or circular colonies of varying sizes.Paenibacillus grows extremely rapidly on culture media, and will overgrow an entire plate in 24 hours from a single point of inoculation. Therefore an exact count is almost impossible to determine.

Vancomycin resistant. Morphologically resembles streptococci. Associated with milk and dairy products. Rarely isolated from human clinical specimens.

Can be found in the intestines of humans and other mammals, manure, polluted water, and soil. Can be an opportunistic pathogen.

Pseudomonas fluorescens encompasses a group of common, nonpathogenic saprophytes that colonize soil, water and plant surface environments. It produces a soluble, greenish fluorescent pigment, particularly under conditions of low iron availability. It is motile by means of multiple polar flagella. P. fluorescens has simple nutritional requirements.

(Flavimonas oryyzihabitans) . Is widely distributed in both nature and the hospital environment. It has been associated with nosocomial (hospital-acquired) infections.

Pseudomonas are widely distributed in the environment and are especially prone to inhabit moist areas. They are also a member of the normal flora of the intestinal tract of humans. It is associated with a variety of infections and is a major cause of nosocomial infections in the hospital environment.

Has been isolated from both clinical and environmental sources, primarily water. It may rarely be an opportunistic pathogen.

This is a Gram negative bacteria in the family Enterobacteriaceae. Serratia species have been isolated from clinical samples but have also been isolated from several environmental specimens such as soil, plates, and water.

Sphingomonas paucimobilis is a gram-negative, rod-shaped, aerobic bacteria. It typically produces yellow-pigmented colonies. It is widely distributed in nature, having been isolated from many different land and water habitats, as well as from plant root systems, clinical specimens, and other sources. It is known as a common component of soap scum.

Normal flora of the skin and mucous membranes. Can also be isolated from dust, water, and food products. Several species are considered as opportunistic pathogens to humans and animals.

Isolated from the environment and animal sources. Occasionally isolated from clinical specimens.