Bacteria Information

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The majority of the information about these bacterial species were obtained from Microbewiki.kenyon.edu. The information may change and evolve over time to include other sources. Click on the name of the Bacterial species to see full description: Overview, Cell structure, metabolism, pathogenicity, ecological roles, genome structure, research, and references.

### *Alcaligenes faecalis*

*Alcaligenes*faecalis*is a species of Gram-negative, rod-shaped bacteria commonly found in*the environment. It was originally named for its first discovery in feces, but was later found to be common in soil, water, and environments in association with humans. While opportunistic infections do occur, the bacterium is generally considered non-pathogenic. When an opportunistic infection does occur, it is usually observed in the form of a urinary tract infection....

### *Bacillus cereus*

*Bacillus* cereus*is a* toxin-producing facultative anaerobic gram-positive bacillus-shaped bacteria. The bacteria is commonly found in the environment, is often found in soil and vegetation, and can be present in foods.  It can quickly multiply at room temperature. There are two main types of an intestinal illness caused by *B.* cereus. O*ne is diarrheal, and one leads more to nausea/vomiting.*B. cereus*has also been implicated in infections of the eye, respiratory* tract, and in wounds. The pathogenicity of *B. cereus*, whether intestinal or non-intestinal, is intimately associated with the production of tissue-destructive exoenzymes. Among these secreted toxins are four hemolysins, three distinct phospholipases, an emesis-inducing toxin, and proteases....

### *Bacillus megaterium*

*Bacillus megaterium* is a gram positive, endospore forming, rod shaped bacteria. It is considered aerobic. It is found in soil and considered a saprophyte. *Bacillus megaterium* is Latin for the big beast because it is an extremely large bacteria, it is about 100 times as large as *E. coli*. Due to its immense size, about 60 micrometers cubed, *B. megaterium* has been used to study structure, protein localization and membranes of bacteria since the 1950’s....

### *Bacillus stearothermophilus*

*Geobacillus stearothermophilus* (or *Bacillus* stearophilus*) is a rod-shaped, Gram-positive, spore-forming bacterium, that* is able to grow either singly or in chains. The cell wall structures of this bacterium are consistent with features found on typical Gram-positive bacterium. That is, they have a thick peptidoglycan layer surrounding their cytoplasmic lipid membrane. However, the *G. stearothermophilus* Gram stain reaction may vary between positive and negative.This bacterium is also motile, aerobic, and both catalase and oxidase positive. The colonies of *G. stearothermophilus* can grow into various shapes and sizes, and in addition, pigments may be formed on certain media....

### ***Bacillus subtilis***

*Bacillus subtilis* cells are rod-shaped, Gram-positive bacteria that are naturally found in soil and vegetation. *Bacillus subtilis* grow in the mesophilic temperature range. The optimal temperature is 25-35 degrees Celsius (Entrez Genome Project). Stress and starvation are common in this environment, therefore, *Bacillus subtilis* has evolved a set of strategies that allow survival under these harsh conditions. One strategy, for example, is the formation of stress-resistant endospores....

### ***Branhamella catarrhalis***

*Moraxella catarrhalis* is a gram negative, diplococcus, aerobic infectious pathogen that is a common cause of upper respiratory, middle ear, and eye infections. It is resistant to many ß-lactam drugs such as penicillin, amoxicillin, and ampicillin. 'M. catarrhalis' can be found commensally in the respiratory tract of some people, living without infections symptoms or promoting host immune response. In adults, the rate of colonization seems to be around 3% of healthy adult population....

### ***Corynebacterium diptheriae***

*Corynebacterium diphtheriae* is a gram-positive, non-motile, aerobic, and rod-shaped bacterium that causes diphtheria. There are four main subspecies that have been recognized: *C. diphtheriae mitis*, *C. diphtheriae intermedius*, *C. diphtheriae gravis*, and *C. diphtheriae belfanti*. *C. diphtheriae gravis* has the fastest generation time, allowing it to impose its toxic effects sooner. They can all be characterized as toxigenic or non-toxigenic, or those causing diphtheria and those that don’t, respectively. Diphtheria is an upper respiratory tract infection initially resulting in a sore throat and mild fever, but can progress to other more serious symptoms if not treated [1]. It can also infect the skin when lesions are exposed to the bacteria.

### ***Corynebacterium pseudodiphtheriticum***

*Corynebacterium pseudodiphtheriticum*, previously designated as *Corynebacterium hofmannii*, is a nonlipophilic, nonfermentive, urease- and nitrate-positive *Corynebacterium* species, which is part of the oropharyngeal bacterial flora.4 As part of the natural microbiota of nares and throat, *C. pseudodiphtheriticum* seems to be able to prevent colonization of epithelia by pathogenic bacteria. Spontaneous elimination of *C. diphtheriae*5 as well as competition with *Staphylococcus aureus* was reported6-9 and based on these observations *C. pseudodiphtheriticum* was discussed as candidate for application as nasal and throat probiotic. In fact, corresponding experiments were carried out with volunteers and showed elimination of *S. aureus* from the nasal cavity.

### ***Corynebacterium xerosis***

*Corynebacterium xerosis* is a commensal organism found in skin and mucous membranes of humans. It is considered an unusual pathogen, and it is rarely found in human and animal clinical samples. Here we describe the isolation of *C. xerosis* from a 4-months-old Pelifolk lamb located in Tesistán, central western Mexico. This microorganism should be considered for differential diagnosis in cutaneous abscessed lesions in sheep, as it represents a zoonotic risk factor for human infection in sheep farms.

### Providencia stuartii

Basic information and growth requiremnts: https://catalog.hardydiagnostics.com/cp\_prod/Content/hugo/Providencia.htm

### **Streptomyces griseus**

S*treptomyces griseus* are gram positive, aerobic, filamentous bacteria. *Streptomyces griseus* is a soil-dwelling bacteria like most of the other species in its genus. S. griseus’ optimal temperature to live in is at 25-35C. The genus *Streptomyces* are also responsible for the “earthy” smell of soil and the fertility of the soil.  *Streptomyces griseus* produces many useful secondary metabolites such as enzyme inhibitors and contribute 70% of naturally-occurring antibiotics