BioChem - DOS

Contributory roles of two L-lactate dehydrogenases for L-lactic acid production in thermotolerant Bacillus coagulans

Scientific reports

Sun, Lifan; Zhang, Caili; Lyu, Pengcheng; Wang, Yanping; Wang, Limin; Yu, Bo

<P>Thermotolerant <I>Bacillus coagulans</I> is considered to be a more promising producer for bio-chemicals, due to its capacity to withstand harsh conditions. Two L-lactate dehydrogenase (LDH) encoding genes (<I>ldh</I>L1 and <I>ldh</I>L2) and one D-LDH encoding gene (<I>ldh</I>D) were annotated from the <I>B. coagulans</I> DSM1 genome. Transcriptional analysis revealed that the expression of <I>ldh</I>L2 was undetectable while the <I>ldh</I>L1 transcription level was much higher than that of <I>ldh</I>D at all growth phases. Deletion of the <I>ldh</I>L2 gene revealed no difference in fermentation profile compared to the wild-type strain, while <I>ldh</I>L1 single deletion or <I>ldh</I>L1<I>ldh</I>L2 double deletion completely blocked L-lactic acid production. Complementation of <I>ldh</I>L1 in the above knockout strains restored fermentation profiles to those observed in the wild-type strain. This study demonstrates <I>ldh</I>L1 is crucial for L-lactic acid production and NADH balance in <I>B. coagulans</I> DSM1 and lays the fundamental for engineering the thermotolerant <I>B. coagulans</I> strain as a platform chemicals producer.</P>

2016

Nature Publishing Group

cc-by

2045-2322

6

pp.37916

10.1038/srep37916

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART76888019

https://www.nature.com/articles/srep37916.pdf