CoxR Directly Represses Alkane Hydroxylase Gene Expression in Caulobacter crescentus

Abstract

Alkanes are commonly found in nature and many gram positive and gram negative bacteria have developed enzymes for degrading them. The alphaproteobacteria Caulobacter crescentus has the CYP153 gene which codes for a medium‐chain alkane hydroxylase in the cytochrome P450 family. However, the regulatory mechanism controlling this gene has not been well‐characterized. A reverse genetics screen found that a deletion in the TetR family coxR gene results in a strain that is sensitive to oxidative stress. We used RNA‐seq and EMSA with Ni‐NTA purified CoxR to determine which genes CoxR directly regulates. Expression of the CYP153, ferredoxin and ferredoxin reductase genes were shown to be upregulated in the coxR deletion strain. Furthermore, CoxR was shown to directly bind to a 35bp region of the CYP153 promoter. In summary, we have shown that the transcription factor CoxR directly represses CYP153 gene expression.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.