Identification of sirtuin and its target as the ribosomal protein S4 in Lactobacillus paracasei

The Journal of General and Applied Microbiology

Naoto Tanaka⁴  Shinji Kawasaki³  Akihito Endo²  Yuh Shiwa¹  Junichi Nakagawa²  Yoichi Niimura³  Sanae Okada⁴  Hotaka Atarashi² 

[1] Genome Research Center, NODAI Research Institute, Tokyo University of Agriculture;Department of Food and Cosmetic Science, Graduate School of Bioindustry, Tokyo University of Agriculture;Department of Bioscience, Tokyo University of Agriculture;Culture Collection Center, NODAI Research Institute, Tokyo University of Agriculture

关键词: acetylated protein substrate;    bacterial sirtuin;    Lactobacillus;    probiotics;    ribosomal protein;   

DOI  :  10.2323/jgam.62.98

学科分类：微生物学和免疫学

来源: Applied Microbiology, Molecular and Cellulrar Biosciences Research Foundation

【 摘 要 】

Sirtuin is a protein with an enzymatic activity of NAD+-dependent protein deacetylation. It was first identified in yeast and its homologous genes have been widely found in various organisms. In bacteria, sirtuin gene was first described as cobB, encoding a cobalamin processing enzyme; and later its potential involvement in regulating acetylation levels of metabolic enzymes, transcription factors, chemotactic proteins and others have been reported. In order to study its physiological relevance in probiotic lactic acid bacteria, we analyzed the whole genome of three L. paracasei strains. All strains tested had sirtuin homolog genes designated hereby as sirA, and one of them had an additional gene designated as sirB. Following confirmation of their coding sequences by individual gene cloning, corresponding recombinant proteins have been generated and purified. The enzymatic characterization revealed that the intrinsic NAD+-dependent deacetylation activity of LpSirA (protein encoded by sirA) is comparable to human SIRT1. Furthermore, by blocking sirtuin activity using nicotinamide in vivo, together with an in vitro deacetylation reaction using recombinant LpSirA, we identified one of the target proteins in the lactic acid bacteria as the 30S ribosomal protein S4 (rpsD product).

【 授权许可】

Unknown