The bacterial formation of trimethylamine (TMA) has been linked to cardiovascular disease. This review focuses on the methods employed to investigate the identity of the bacteria responsible for the formation of TMA from dietary choline and carnitine in the human gut. Recent studies have revealed the metabolic pathways responsible for bacterial TMA production, primarily the anaerobic glycyl radical-containing, choline-TMA lyase, CutC and the aerobic carnitine monooxygenase, CntA. Identification of these enzymes has enabled bioinformatics approaches to screen both human-associated bacterial isolate genomes and whole gut metagenomes to determine which bacteria are responsible for TMA formation in the human gut. We centre on several key methodological aspects for identifying the TMA-producing bacteria and report how these pathways can be identified in human gut microbiota through bioinformatics analysis of available bacterial genomes and gut metagenomes.

三甲胺（TMA）的细菌形成与心血管疾病有关。这篇综述着重于研究人类肠道中由饮食胆碱和肉碱形成TMA的细菌身份的研究方法。最近的研究已经揭示了导致细菌TMA产生的代谢途径，主要是含厌氧甘氨酰自由基的胆碱-TMA裂解酶CutC和好氧肉碱单加氧酶CntA。这些酶的鉴定使生物信息学方法能够筛选与人类相关的细菌分离基因组和整个肠道元基因组，从而确定哪些细菌导致了人类肠道中TMA的形成。