Indian Journal of Science and Technology

Abstract

Para crystalline layer is a monomolecular outermost protein layer in bacteria and archiae, credit of protein or glycoprotein subunits and has crystalline biopolymer structure. Para crystalline -layer protects bacteria to phagocytosis and prohibit the entry of some biomolecule -for example antibiotics- and adhesion to matrix proteins, is one of virulence agents and layer producer. Para crystalline layer have application potential in biotechnology, molecular nanotechnology, and biomimetics. The research was performed with laboratory method in 2005-2007 years, in Azzahra hospital and Isfahan University. In this research, 26 Bacillus cereus strains were studied. Identification of bacteria, was performed with microbiological methods: staining, chemical test, using differential and selective media. Isolation of Bacillus cereus strains was performed on Selective Agar, and cultured in TSA, for 16 hours, under aerobic condition. Then subjected to the separation of surface proteins and electrophoresed along with molecular weight marker. Para crystalline layer in B. cereus has 97 KD MW. Out of 26 B. cereus strain, 14 strain produced Para crystalline layer and 12 strain don’t have Para crystalline -layer. Out of 13 isolates from staff hand, 11 sample (84/6%) and from 13 isolates from hospital surfaces, 1 sample (7/7%) have produced Para crystalline layer. Keywords: Para Crystalline Layer, Bacillus cereus, nosocomial infections