Abstract
There are exponential increases in the number of microbes acquired or which build resistance against various antibiotics. In this study we show that, a single strain, (Escherichia coli ATCC 8739 found in the protein database) has different beta-lactamases. By investigating the Blast protein database for the existence of one of that different E. coli beta-lactamases, the result shows that this protein can be found in hundreds of different microbes with 100% identity. Multiple alignment for both of beta-lactamases of four E. coli strains alone or with sixteen other sequences represent beta-lactamases of the classes A, B, C and D have been generated. A Phylogenic tree for the used beta-lactamases shows that the four E. coli beta-lactamases clustered with those of class C. Protein models for the four E. coli beta-lactamases have been built from beta-lactamases 3D structure using software modeller. Further more, the purpose of this study is to investigate other resistance mechanism. A model has been built to clarify the role of biofilm in the resistance elevation which can mimic what has been happened in reality. Alginate isolated from Pseudomonas aeruginosa 9027 has been produced, purified and used. E. coli and Bacillus stearothermophilus ATCC 7953 were sensitive to Penicillin or streptomycin has been used to show the role of biofilm in resistance.