Detection Of ESBLs Genetype Produced By Shigella From Chicken And Tentative Treatments Of Its Infection

MIC of common antibiotics against shigella isolated from chicken were determined by the ameliorative two fold dilution method ,the ESBLs produced by shigella were detected by double slips synergy and its phenotypes were also made sure with PCR in this paper.The treatment results of compound suspension preparation of ceftiofur which were tentatively made by our laboratory against diseases infected by shigella produced ESBLs were observed, in order to understand the current situation and mechanism of drugs'resistance and investigated molecule mechanism of ita drugs'resistance. theories based on the experiment were offered for clinical trsatments,new thoughts on exploitation of new veterinary drugs were offered at the same time.The results of the detection of BLA and ESBLs showed that shigella clinical strains isolated from chichen had produced BLA by nitrocefin disc test, but none of AmpC . ESBLs was found by double-disc synergy method. The primer was designed for the ESBLs produced by shigella and amplification by PCR,then cloning and sequencing, an analysis was executed by contrasting with the sequence of U48775 with a software called Dnastar MegAlign Sequence, the homology gene with 99.2% was identitied to TEM-1(U48775), the result revealed the 287-amino-acid protein differing by three amino acid substitutions from β-lactamase TEM-1(Asp33 Glu, Thr186 Ala, Arg271Gln),It harbored a TEM -116 type gene with 99.8% identity to AY903309 (TEM-116), Amino acid differences in comparison to the amino acid sequence of ESBLs TEM-116 with Dnastar MegAlign Sequence Distances were found differing only one(Ser 51 Glu),although at the point 403 T changed into C, but it should be silent mutation and not lead to the amino acid changement. The genetype of enzyme was called TEM-1V temporarily because there were an amino acid which was different with sequence of TEM-116 and got serial-number DQ211973 by uploading to Genbank.The results of drug susceptibility in vitro showed that susceptibility of single...