bacillus pumilus

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Contents: Main TOPIC : Bacillus pumilus 1) Bacillus pumilus 2) Genome and cell structure 3) Scientific classification Kingdom Bacteria Phylum: Firmicutes Class: Bacilli Order: Bacillates Family: Bacillaceae Genes : Bacillus pumilus Binomial name : Bacillus pumilus 4) Ecology and Pathogenesis 5) B.Pumilus Human infection 6) Environmental roles Cell wall: Use as model organism Industrial significance Ecological significance: Clinical significance:

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Page 1: Bacillus pumilus

Contents: Main TOPIC : Bacillus pumilus

1) Bacillus pumilus

2) Genome and cell structure

3) Scientific classification

Kingdom Bacteria

Phylum: Firmicutes

Class: Bacilli

Order: Bacillates

Family: Bacillaceae

Genes : Bacillus pumilus

Binomial name: Bacillus pumilus

4) Ecology and Pathogenesis

5) B.Pumilus Human infection

6) Environmental roles

Cell wall: Use as model organism Industrial significance Ecological significance: Clinical significance: In Vitro Assessment of Marine Bacillus for Use as Livestock Probiotics References

what is bacillus pumilus?

Page 2: Bacillus pumilus

Bacillus pumilus is a Gram-positive. These are Rod shape bacteria. Bacillus pumilus  aerobic, spore-forming bacillus . commonly found in soil. B. pumilus spores—with the exception of mutant strain ATCC

7061—generally show high resistance to environmental stresses, Show resistance to, including UV light exposure, desiccation, and the presence

of oxidizers such as hydrogen peroxide. Strains of B. pumilus found at the NASA Jet Propulsion Laboratory were found to be

particularly resistant to hydrogen peroxide. A strain of B. pumilus isolated from black tiger shrimp (Penaeus monodon) was found to

have high salt tolerance and to inhibit the growth of marine pathogens, including Vibrio alginolyticus, when cultured together.Bacillus pumilus:

colonies on agar smooth and slightly yellowish; can not grow anaerobically; can not hydrolyze starch; can not reduce nitrate.

B. pumilus contains one circular chromosome Each chromosomes having 4000 genes and 3600-3900 proteins . Caused infection both plants and animals.

Genome and cell structure

B. pumilus contains one circular chromosome including about 4000 genes and 3600-3900 proteins with varying length in the range of 3.7 to 3.8 Mbp. 41% of the DNA base pairs in B. pumilus are G-C. The cellular structure of B. pumilus is similar to other Bacillus species such as B. subtilis, B. megaterium, and B. cereus, the outer layer of the peptidoglycan cross-links in B. pumilus is covered by teichoic and lipoteichoic acids same as the most other Gram positive bacteria.

These acids contain polyglycosyl phosphates with mono- and disaccharides as their monomers that can play a role in adhesion to different surfaces like the host cells.

On the other hand, these phosphate groups on the surface of B. pumilus can provide net negative charge on the cell surface that allowing to capture some essential cations such as Ca2+ and Mg2+ that are necessary for cell life.

Bacillus pumilus

Page 3: Bacillus pumilus

Scientific classification

Kingdom : Bacteria

Phylum: Firmicutes

Class: Bacilli

Order: Bacillates

Family: Bacillaceae

Genes : Bacillus pumilus

Binomial name: Bacillus pumilus

Ecology and Pathogenesis

acillus pumilus participates in a wide range of symbiotic relationships. B. pumilus can function as a plant growth promoting rhizobacteria within the rhizosphere of agriculturally significant plants such as red peppers (Capsicum annuum L.) and wheat (Triticum aestivum). In wheat, B. pumilus also induces plant resistance to Take-all (Gaeumannomyces graminis), a fungal disease which can significantly damage wheat crops .

Additionally, B. pumilus is thought to function as a plant growth promoting endophyte in Vitis vinifera grape plants . Penaeus monodon, black tiger shrimp, can host Bacillus pumilusin the gut, where it inhibits infections by Vibrio harveyi, V. alginolyticus, and V. parahaemolyticus, all of which are known to be significant bacterial pathogens of shrimp .

B. pumilus is significant to ecosystem biochemistry because it functions as a nitrogen fixing bacteria capable of metabolically transforming molecular nitrogen (N2) into ammonia (NH3) .

Human infection by Bacillus pumilus is rare, however in 2006 B. pumilus in rice was found to be responsible for 3 cases of food poisoning. The isolated strain produced a complex of lipopeptides called pumilacidins, known to have toxic effects on epithelial cells.

The symptoms that resulted from infection included dizziness, headache, chills, back pain, stomach cramps, and diarrhea.

Furthermore, in 2007 a report summarizing 3 case studies was published concluding that a strain of Bacillus pumilus was responsible for the development of cutaneous lesions morphologically similar to those caused by Bacillus anthracis.

Human infection: Human infection due to Bacillus pumilus is exceptional. According to the report they reported 3 cases of cutaneous infection caused by B. pumilus that occurred in 3 shepherds, 2 of whom

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were members of the same family. The lesions appeared to have a morphology similar to that of cutaneous anthrax lesions. Two patients were cured after treatment with amoxicillin-clavulanate, and the third patient was cured after prolonged treatment with ciprofloxacin. To our knowledge, primary cutaneous infection due to B. pumilus has not been reported. B. pumilus should be considered in patients who develop lesions suggestive of cutaneous anthrax.

The genus Bacillus consists of a heterogenic group of gram-positive, endospore-forming, rod-shaped, facultative anaerobic bacteria. Bacillus anthracis is the causative agent of anthrax. The disease can occur in different forms . By far the most common is cutaneous anthrax, which accounts for>90% of all human cases. Cutaneous infection usually results from contact with infected animals or animal products (such as hides or wool) contaminated with B. anthracis spores.

Bacillus species other than B. anthracis produce spores that are widespread in the environment, and isolation from a specimen may represent contamination. However, it is well recognized that these organisms are capable of causing serious human infections, including endocarditis, sepsis, meningitis, pneumonia, endophthalmitis, and surgical wound infections . Primary cutaneous infection due to Bacillus species other than B. anthracis is exceptional.

We report 3 cases of cutaneous infection due to Bacillus pumilus that occurred in 3 shepherds, 2 of whom were members of the same family. The lesions had a morphology similar to that of cutaneous anthrax lesions. To our knowledge, primary cutaneous infection caused by B. pumilus has not been reported.

Environmental roles Cell wall:

The cell wall of Bacillus is a structure on the outside of the cell that forms the second barrier between the bacterium and the environment, and at the same time maintains the rod shape and withstands the pressure generated by the cell's turgor.

The cell wall is composed of teichoic and teichuronic acids. B. subtilis is the first bacterium for which the role of an actin-likecytoskeleton in cell shape determination and peptidoglycan synthesis was identified, and for which the entire set of peptidoglycan-synthesizing enzymes was localised. The role of the cytoskeleton in shape generation and maintenance is important

Use as model organism:

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Bacillus subtilis is one of the best understood prokaryotes, in terms of molecular and cellular biology. Its superb genetic amenability and relatively large size have provided the powerful tools required to investigate a bacterium from all possible aspects. Recent improvements in fluorescence microscopy techniques have provided novel and amazing insight into the dynamic structure of a single cell organism. Research on B. subtilis has been at the forefront of bacterial molecular biology and cytology, and the organism is a model for differentiation, gene/protein regulation, and cell cycle events in bacteria

Industrial significance

Many Bacillus species are able to secrete large quantities of enzymes. Bacillus amyloliquefaciens is the source of a natural antibiotic protein barnase (a ribonuclease), alpha amylase used in starch hydrolysis, the protease subtilisin used with detergents, and the BamH1 restriction enzyme used in DNA research.

A portion of the Bacillus thuringiensis genome was incorporated into corn (and cotton) crops. The resulting GMOs are therefore resistant to some insect pests.

Ecological significance:

Bacillus species are almost ubiquitous in nature, e.g. in soil, but also occur in extreme environments such as high pH (B. alcalophilus), high temperature (B. thermophilus), or high salt (B. halodurans). B. thuringiensis produces a toxin that can kill insects and thus has been used as insecticide.

Clinical significance:

Two Bacillus species are considered medically significant: B. anthracis, which causes anthrax, and B. cereus, which causesfood poisoning similar to that caused by Staphylococcus.[6] A third species, B. thuringiensis, is an important insect pathogen, and is sometimes used to control insect pests. The type species is B. subtilis, an important model organism. It is also a notable food spoiler, causing ropiness in bread and related food. Some environmental and commercial strains of B. coagulans may play a role in food spoilage of highly acidic, tomato-based products.

An easy way to isolate Bacillus species is by placing nonsterile soil in a test tube with water, shaking, placing in meltedmannitol salt agar, and incubating at room temperature for at least a day. Colonies are usually large, spreading, and irregularly shaped. Under the microscope, the Bacillus cells appear as rods, and a substantial portion of the cells usually contain oval endospores at one end, making it bulge.

In Vitro Assessment of Marine Bacillus for Use as Livestock Probiotics:

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Six antimicrobial-producing seaweed-derived Bacillus strains were evaluated in vitro as animal probiotics, in comparison to two Bacillus from an EU-authorized animal probiotic product. Antimicrobial activity was demonstrated on solid media against porcine Salmonella and E. coli. The marine isolates were most active against the latter, had better activity than the commercial probiotics and Bacillus pumilus WIT 588 also reduced E. coli counts in broth. All of the marine Bacillus tolerated physiological concentrations of bile, with some as tolerant as one of the probiotics. Spore counts for all isolates remained almost constant during incubation in simulated gastric and ileum juices.

All of the marine Bacillus grew anaerobically and the spores of all except one isolate germinated under anaerobic conditions. All were sensitive to a panel of antibiotics and non harbored Bacillus enterotoxin genes but all, except B. pumilus WIT 588, showed some degree of β-hemolysis. However, trypan blue dye exclusion and xCELLigence assays demonstrated a lack of toxicity in comparison to two pathogens; in fact, the commercial probiotics appeared more cytotoxic than the majority of the marine Bacillus. Overall, some of the marine-derived Bacillus, in particular B. pumilus WIT 588, demonstrate potential for use as livestock probiotics.

19/10/2015

1.  Euzéby JP (2008). "Bacillus". List of Prokaryotic names with Standing in Nomenclature. Archived from the original on 14 December 2008. Retrieved2008-11-18.

2. Jump up ̂  Ambrosiano N (1999-06-30). "Lab biodetector tests to be safe, public to be well informed". Press release. Los Alamos National Labs. Retrieved2008-11-18.[dead link]

3. Jump up ̂  Ehrenberg CG (1835). Physikalische Abhandlungen der Koeniglichen Akademie der Wissenschaften zu Berlin aus den Jahren 1833–1835. pp. 145–336.