title: Biochemical analyses of ppGpp effect on adenylosuccinate synthetases, key enzymes in purine biosynthesis in rice.
abstract: The ppGpp-signaling system functions in plant chloroplasts. In bacteria, a negative effect of ppGpp on adenylosuccinate synthetase (AdSS) has been suggested. Our biochemical analysis also revealed rice AdSS homologs are apparently sensitive to ppGpp. However, further investigation clarified that this phenomenon is cancelled by the high substrate affinity to the enzymes, leading to a limited effect of ppGpp on adenylosuccinate synthesis.
authors.affiliation: a Graduate School of Science and Engineering , Ehime University , Matsuyama , Japan.
authors.forename: Yuhta
authors.initials: Y
authors.lastname: Nomura
authors.forename: Akira
authors.initials: A
authors.lastname: Nozawa
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Tozawa
mesh_terms: D000265:Adenylosuccinate Synthase / Q000378:metabolism*; D001412:Bacillus subtilis / Q000201:enzymology; D004926:Escherichia coli / Q000201:enzymology; D006159:Guanosine Tetraphosphate / Q000737:chemistry / Q000494:pharmacology*; D007700:Kinetics; D012275:Oryza / Q000201:enzymology* / Q000378:metabolism; D011687:Purines / Q000096:biosynthesis*; D017386:Sequence Homology, Amino Acid
chemical_list: D011687:Purines; D006159:Guanosine Tetraphosphate; D000265:Adenylosuccinate Synthase; C030985:purine
keywords: Oryza sativa; adenylosuccinate synthetase; chloroplast; ppGpp; purine biosynthesis