Tupa Peter Robert, Masuda Hisako
J Mol Microbiol Biotechnol. 2018;28(3):107-115. doi: 10.1159/000490494. Epub 2018 Aug 28.
While growing on propane as a sole source of carbon, many strains cometabolically degrade environmental pollutants, such as ethers and chlorinated hydrocarbons. To gain insights into the molecular basis behind such a high metabolic versatility of propanotrophs, we examined the propane-inducible protein expression patterns of 2 soil actinobacteria that are known to degrade a variety of ethers (i.e., Mycobacterium sp. strain ENV421 and Rhodococcus sp. strain ENV425). In both strains, soluble diiron monooxygenase(s), that would catalyze the first step of the pathway, were induced by propane. However, despite their phylogenetic similarity, different sets of additional putative propane oxygenases (e.g., cytochrome P450 and particulate methane monooxygenases) were overexpressed in the 2 strains. They also diverged in the expression of enzymes responsible for downstream reactions. This study revealed a diversity of expression of putative propane oxygenases, which may be responsible for xenobiotic degradation, as well as a variety of metabolic pathways for propane in these bacterial species.
在以丙烷作为唯一碳源生长时，许多菌株会共代谢降解环境污染物，如醚类和氯代烃。为深入了解丙烷营养菌这种高代谢多样性背后的分子基础，我们研究了2种已知能降解多种醚类的土壤放线菌（即分枝杆菌属菌株ENV421和红球菌属菌株ENV425）的丙烷诱导蛋白表达模式。在这两种菌株中，可催化该途径第一步的可溶性双铁单加氧酶由丙烷诱导产生。然而，尽管它们在系统发育上相似，但在这两种菌株中，不同组别的其他假定丙烷加氧酶（如细胞色素P450和颗粒性甲烷单加氧酶）均有过表达。它们在负责下游反应的酶的表达上也存在差异。这项研究揭示了可能负责异生物质降解的假定丙烷加氧酶的表达多样性，以及这些细菌物种中丙烷的多种代谢途径。
