D-Amino acids and D-Tyr-tRNA(Tyr) deacylase: stereospecificity of the translation machine revisited.
Until 30 years ago, it had been considered that D-amino acids were excluded from living systems except for D-amino acids in the cell wall of microorganisms. However, D-amino acids, in the form of free amino acids, peptides and proteins, were recently detected in various living organisms from bacteria to mammals. The extensive distribution of bio-functional D-amino acids challenges the current concept of protein synthesis: more attention should be paid to the stereospecificity of the translation machine. Besides aminoacyl-tRNA synthetases, elongation factor Tu and some other mechanisms, D-Tyr-tRNA(Tyr) deacylases provide a novel checkpoint since they specifically recycle misaminoacylated D-Tyr-tRNA(Tyr) and some other D-aminoacyl-tRNAs. Their unique structure represents a new class of tRNA-dependent hydrolase. These unexpected findings have far-reaching implications for our understanding of protein synthesis and its origin.
Yang
Hongbo
H
Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, 5 Dong Dan San Tiao, 100005 Beijing, PR China.
Zheng
Gen
G
Peng
Xiaozhong
X
Qiang
Boqin
B
Yuan
Jiangang
J
D000596:Amino Acids / Q000737:chemistry* / Q000378:metabolism*; D019881:Aminoacyltransferases / Q000737:chemistry* / Q000378:metabolism*; D000818:Animals; D020134:Catalytic Domain; D006801:Humans; D008958:Models, Molecular; D014176:Protein Biosynthesis; D011487:Protein Conformation; D012346:RNA, Transfer, Amino Acyl / Q000737:chemistry / Q000378:metabolism; D013237:Stereoisomerism; D013379:Substrate Specificity
D000596:Amino Acids; D012346:RNA, Transfer, Amino Acyl; D019881:Aminoacyltransferases; C120167:D-tyrosine tRNA(Tyr) deacylase