Proteus mirabilis

Contents [hide] 1 Genome structure 2 Cell structure and metabolism 3 Ecology 4 Pathology 5 Application to Biotechnology 6 Current Research 7 References

Description and Significance [edit]

Proteus Mirabilis is a gram-negative, rod-shapped bacteria belonging to the enterobacteriaceae family. It is facultatively anaearobic meaning that it does not require oxygen for survival and reproduction and may even die in the presence of oxygen. Proteus Mirabilis are found in moist habitats, such as water and soil. They are however mostly found in putrid meat, infusions, and abscesses. They are also found inhabiting urinary tracts of human where it is believed to cause urinary tract infections associated with formation of renal and bladder calculi, often known as bladder stones. In fact, they cause 90% of proteus infections in humans and Its most common site of infection is the urinary tract.

Genome structure [edit]

Proteus Mirabilis contains an extracytoplamic outer membrane, which is a common characteristic of other gram-negative bacterias. In addition, the outer membrane contains a lipid bilayer, lipoproteins, polysaccharides, and lipopolysaccharides. Infection depends on the interaction between the infecting organism and the host defence mechanisms. Various components of the membrane interplay with the host to determine virulence. Inoculum size is important and has a positive correlation with the risk of infection.

The genome of Proteus Mirabilis is .063 Mb long and has a G+C content of 38.88%. There is a single plasmid consisting of 36,289 nucleotides. Annotation of the genome identified 3,685 coding sequences and seven rRNA loci. Analysis of the sequence confirmed the presence of previously identified virulence determinants, as well as a contiguous 54-kb flagellar regulon and 17 types of fimbriae. Genes encoding a potential type III secretion system were identified on a low-G+C-content genomic island containing 24 intact genes that appear to encode all components necessary to assemble a type III secretion system needle complex. In addition, the P. mirabilis HI4320 genome possesses four tandem copies of the zapE metalloprotease gene, genes encoding six putative autotransporters, an extension of the atf fimbrial operon to six genes, including an mrpJ homolog, and genes encoding at least five iron uptake mechanisms, two potential type IV secretion systems, and 16 two-component regulators.

Cell structure and metabolism [edit]

Proteus can display two different morphological and physiological forms, known as swimmer cells and swarmer cells. In aqueous suspension Proteus mirabilis is found in the swimmer state, which is a small rod-like cells1 to 2 μm in length motile by 8 to 10 flagella. On contact with a surface, Proteus has the ability to convert to the swarmer state. The bacterial cells elongate dramatically to form highly flagellated filaments 20 to 80 μm in length. These cells line up in parallel to form rafts that are able to move rapidly over surfaces en masse.