Isolation of Colistin Resistant genes in Pandrug Resistant Acinetobacter baumannii (PDRAB) by Systemic Approach

• Main Authors: Yo-Long Tian, 田游榮
• Other Authors: Kai-Chih Chang
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/99335741019599338598

碩士 === 慈濟大學 === 醫學生物技術研究所 === 95 === Acinetobacter baumanni can cause several severe syndromes such as pneumonia, bacteremia, meningitis, urinary tract infection and wound infection. There was a new Acinetobacter baumannii recently isolated and found to be resistant to commonly used antibiotics and named Pandrug-Resistant Acinetobacter baumannii (PDRAB). At present, colistin can effectively treat Acinetobacter baumannii. Although there is sporadically colistin resistant strains found clinically. In order to investigate the genes associated with colistin resistance, we planed to isolate colistin resistant genes by systemic approach. Firstly, we collected colistin resistant PDRAB and constructed a PDRAB gene expression library. Next, we used PCR and DNA sequence methods to test whether this expression library is representative. Then we used solid LB agar consisted of 1 μg/ml colistin and 50 μg/ml kanamycin to isolate colistin resistant E. coli XLOLR strain, extracted out plasmids carring partial Acinetobacter baumannii chromosome fragment and retransform these plasmids to another XLOLR strain. Finally, we will test colistin minimal inhibition concentration (MIC) of this transformed strain, it enables me to confirm that this gene of PDRAB is truly associated with colistin resistance if there is an elevation of colistin MIC. In addition, according to the review papers, we found three drug resistance genes, emrB, rstB and ACIAD2238, may be associated with colistin resistance in Acinetobacter. We disrupted these genes independently in colistin resistance strain 33305CR, and found that emrB and rstB were associated with colistin resistance.