Reaction: ATP + [L-Asp(4-L-Arg)]n + L-Asp = ADP + phosphate + [L-Asp(4-L-Arg)]n—L-Asp
For diagram click here.
Glossary: cyanophycin = [L-Asp(4-L-Arg)]n = N-β-aspartylarginine = [L-4-(L-arginin-2-N-yl)aspartic acid]n = poly{N4-[(1S)-1-carboxy-4-guanidinobutyl]-L-asparagine}
Other name(s): CphA (ambiguous); CphA1 (ambiguous); CphA2 (ambiguous); cyanophycin synthetase (ambiguous); multi-L-arginyl-poly-L-aspartate synthase (ambiguous)
Systematic name: cyanophycin:L-aspartate ligase (ADP-forming)
Comments: Requires Mg2+ for activity. Both this enzyme and EC 6.3.2.30, cyanophycin synthase (L-arginine-adding), are required for the elongation of cyanophycin, which is a protein-like cell inclusion that is unique to cyanobacteria and acts as a temporary nitrogen store [2]. Both enzymes are found in the same protein but have different active sites [2,4]. Both L-Asp and L-Arg must be present before either enzyme will display significant activity [2].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Aboulmagd, E., Oppermann-Sanio, F.B. and Steinbüchel, A. Molecular characterization of the cyanophycin synthetase from Synechocystis sp. strain PCC6308. Arch. Microbiol. 174 (2000) 297-306. [PMID: 11131019]
2. Aboulmagd, E., Oppermann-Sanio, F.B. and Steinbüchel, A. Purification of Synechocystis sp. strain PCC6308 cyanophycin synthetase and its characterization with respect to substrate and primer specificity. Appl. Environ. Microbiol. 67 (2001) 2176-2182. [PMID: 11319097]
3. Allen, M.M., Hutchison, F. and Weathers, P.J. Cyanophycin granule polypeptide formation and degradation in the cyanobacterium Aphanocapsa 6308. J. Bacteriol. 141 (1980) 687-693. [PMID: 6767688]
4. Berg, H., Ziegler, K., Piotukh, K., Baier, K., Lockau, W. and Volkmer-Engert, R. Biosynthesis of the cyanobacterial reserve polymer multi-L-arginyl-poly-L-aspartic acid (cyanophycin): mechanism of the cyanophycin synthetase reaction studied with synthetic primers. Eur. J. Biochem. 267 (2000) 5561-5570. [PMID: 10951215]
5. Ziegler, K., Deutzmann, R. and Lockau, W. Cyanophycin synthetase-like enzymes of non-cyanobacterial eubacteria: characterization of the polymer produced by a recombinant synthetase of Desulfitobacterium hafniense. Z. Naturforsch. [C] 57 (2002) 522-529. [PMID: 12132696]
6. Ziegler, K., Diener, A., Herpin, C., Richter, R., Deutzmann, R. and Lockau, W. Molecular characterization of cyanophycin synthetase, the enzyme catalyzing the biosynthesis of the cyanobacterial reserve material multi-L-arginyl-poly-L-aspartate (cyanophycin). Eur. J. Biochem. 254 (1998) 154-159. [PMID: 9652408]