Differential expression of Elizabethkingia anophelis to cefotaxime and imipenem
Abstract
Elizabethkingia anophelis is a beta-lactam antibiotic resistant bacterium that uses a variety of mechanisms to express this resistance. It is currently unknown how E. anophelis responds when exposed to different beta-lactam antibiotics and what genes will up or down regulate different genes in order to express antibiotic resistance. When exposed to cefotaxime it appears that E. anophelis will up regulate the production of 4 putative RND efflux pumps along with slight up regulation of a single putative peptidoglycan synthesis protein. This is done in conjunction with a relevant increase fold change in the beta-lactamase BlaB by a factor of +1.5 and an average decreases of -2.33 in the production of GOB, CME, and putative beta-lactamases TLA and Open Reading frame 666. However, when exposed to imipenem E. anophelis will instead down regulate the production of RND efflux pumps, and slightly up regulate the production of a single peptidoglycan synthesis protein. This combined with a decrease in production of BlaB and CME and a relevant increase GOB and ORF666. Both GOB and ORF666 increased by an average fold change of +2.1 with a mRNA count increase of +1,552 leads to a unique response. This difference in the change in the expression of beta-lactamases, peptidoglycan synthesis and efflux pumps under cefotaxime and imipenem conditions shows different responses within a cell to when reaction with different beta-lactam antibiotics. Finally, the observed response by ORF666 suggests that this putative beta-lactamase may play an important role in the resistance of E. anophelis to imipenem, and future work is needed to establish if this is a functional beta-lactamase.