Abstract
Glutathione synthetase catalyses the ATP-dependent ligation of gamma-glutamylcystene with glycine to form glutathione. Amino acid sequence comparisons between the Arabidopsis and the Escherichia coli proteins suggested that a region, identified as a small flexible loop that covers the active site of the E. coli protein, might be conserved in the eukaryotic protein. Three site-directed mutations in the Arabidopsis protein were generated to test this hypothesis. Two mutations within the conserved region (Lys367/ Pro368-->Asn/Ser and Gly374-->Val) inactivated the enzyme in an in vivo assay based on cadmium resistance in S. pombe, and in an in vitro assay of the activity of the enzyme expressed in E. coli. A third mutation outside of this conserved region (Leu363-->Glu) had a smaller effect in both assays. These results are consistent with the idea that this glycine-rich loop in the Arabidopsis and E. coli proteins might serve the same function in covering the active site of the enzyme.
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- Basi G., Schmid E., Maundrell K. TATA box mutations in the Schizosaccharomyces pombe nmt1 promoter affect transcription efficiency but not the transcription start point or thiamine repressibility. Gene. 1993 Jan 15;123(1):131–136. doi: 10.1016/0378-1119(93)90552-e. [DOI] [PubMed] [Google Scholar]
- Fan C., Moews P. C., Shi Y., Walsh C. T., Knox J. R. A common fold for peptide synthetases cleaving ATP to ADP: glutathione synthetase and D-alanine:d-alanine ligase of Escherichia coli. Proc Natl Acad Sci U S A. 1995 Feb 14;92(4):1172–1176. doi: 10.1073/pnas.92.4.1172. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gali R. R., Board P. G. Sequencing and expression of a cDNA for human glutathione synthetase. Biochem J. 1995 Aug 15;310(Pt 1):353–358. doi: 10.1042/bj3100353. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Habenicht A., Hille S., Knöchel W. Molecular cloning of the large subunit of glutathione synthetase from Xenopus laevis embryos. Biochim Biophys Acta. 1993 Sep 23;1174(3):295–298. doi: 10.1016/0167-4781(93)90202-o. [DOI] [PubMed] [Google Scholar]
- Howden R., Andersen C. R., Goldsbrough P. B., Cobbett C. S. A cadmium-sensitive, glutathione-deficient mutant of Arabidopsis thaliana. Plant Physiol. 1995 Apr;107(4):1067–1073. doi: 10.1104/pp.107.4.1067. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Howden R., Goldsbrough P. B., Andersen C. R., Cobbett C. S. Cadmium-sensitive, cad1 mutants of Arabidopsis thaliana are phytochelatin deficient. Plant Physiol. 1995 Apr;107(4):1059–1066. doi: 10.1104/pp.107.4.1059. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huang C. S., He W., Meister A., Anderson M. E. Amino acid sequence of rat kidney glutathione synthetase. Proc Natl Acad Sci U S A. 1995 Feb 14;92(4):1232–1236. doi: 10.1073/pnas.92.4.1232. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kato H., Tanaka T., Yamaguchi H., Hara T., Nishioka T., Katsube Y., Oda J. Flexible loop that is novel catalytic machinery in a ligase. Atomic structure and function of the loopless glutathione synthetase. Biochemistry. 1994 May 3;33(17):4995–4999. doi: 10.1021/bi00183a001. [DOI] [PubMed] [Google Scholar]
- Maundrell K. Thiamine-repressible expression vectors pREP and pRIP for fission yeast. Gene. 1993 Jan 15;123(1):127–130. doi: 10.1016/0378-1119(93)90551-d. [DOI] [PubMed] [Google Scholar]
- Mutoh N., Hayashi Y. Isolation of mutants of Schizosaccharomyces pombe unable to synthesize cadystin, small cadmium-binding peptides. Biochem Biophys Res Commun. 1988 Feb 29;151(1):32–39. doi: 10.1016/0006-291x(88)90555-4. [DOI] [PubMed] [Google Scholar]
- Mutoh N., Nakagawa C. W., Ando S., Tanabe K., Hayashi Y. Cloning and sequencing of the gene encoding the large subunit of glutathione synthetase of Schizosaccharomyces pombe. Biochem Biophys Res Commun. 1991 Nov 27;181(1):430–436. doi: 10.1016/s0006-291x(05)81437-8. [DOI] [PubMed] [Google Scholar]
- Rauser W. E. Phytochelatins and related peptides. Structure, biosynthesis, and function. Plant Physiol. 1995 Dec;109(4):1141–1149. doi: 10.1104/pp.109.4.1141. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rawlins M. R., Leaver C. J., May M. J. Characterisation of an Arabidopsis thaliana cDNA encoding glutathione synthetase. FEBS Lett. 1995 Nov 27;376(1-2):81–86. doi: 10.1016/0014-5793(95)01253-1. [DOI] [PubMed] [Google Scholar]
- Schuler G. D., Altschul S. F., Lipman D. J. A workbench for multiple alignment construction and analysis. Proteins. 1991;9(3):180–190. doi: 10.1002/prot.340090304. [DOI] [PubMed] [Google Scholar]
- Tanaka T., Kato H., Nishioka T., Oda J. Mutational and proteolytic studies on a flexible loop in glutathione synthetase from Escherichia coli B: the loop and arginine 233 are critical for the catalytic reaction. Biochemistry. 1992 Mar 3;31(8):2259–2265. doi: 10.1021/bi00123a007. [DOI] [PubMed] [Google Scholar]
- Tanaka T., Yamaguchi H., Kato H., Nishioka T., Katsube Y., Oda J. Flexibility impaired by mutations revealed the multifunctional roles of the loop in glutathione synthetase. Biochemistry. 1993 Nov 23;32(46):12398–12404. doi: 10.1021/bi00097a018. [DOI] [PubMed] [Google Scholar]
- Wang C. L., Oliver D. J. Cloning of the cDNA and genomic clones for glutathione synthetase from Arabidopsis thaliana and complementation of a gsh2 mutant in fission yeast. Plant Mol Biol. 1996 Sep;31(6):1093–1104. doi: 10.1007/BF00040827. [DOI] [PubMed] [Google Scholar]
- Yamaguchi H., Kato H., Hata Y., Nishioka T., Kimura A., Oda J., Katsube Y. Three-dimensional structure of the glutathione synthetase from Escherichia coli B at 2.0 A resolution. J Mol Biol. 1993 Feb 20;229(4):1083–1100. doi: 10.1006/jmbi.1993.1106. [DOI] [PubMed] [Google Scholar]