Catalytic and regulatory properties of sulphur metabolizing enzymes in cyanobacterium Synechococcus elongatus PCC 7942.

Abstract

Synechococcus elongatus PCC 7942 was able to grow with several S sources. The sulphur metabolizing enzymes viz. ATP sulphurylase, cysteine synthase, thiosulphate reductase and L- and D-cysteine desulphydrases were regulated by sulphur sources, particularly by sulphur amino acids and organic sulphate esters. Sulphur starvation reduced ATP sulphurylase and cysteine synthase whereas reduced glutathione appreciated Cys degradation activity. With partially purified enzymes apparent Km values for sulphate, ATP, D- and L-Cys, thiosulphate, sulphide and O-acetyl serine were in a range of 12-50 microM. p-Nitrophenyl sulphate inhibited ATP sulphurylase competitively. Met was a feedback inhibitor of several key enzymes.

• Authors: Anuradha Jain, Deepti Verma, Divya Bagchi
• Journal: Indian journal of experimental biology (Indian J Exp Biol) Vol. 44 Issue 9 Pg. 767-72 (Sep 2006) ISSN: 0019-5189 [Print] India
• PMID: 16999035 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Enzyme Inhibitors
• Sulfur Compounds
• Oxidoreductases Acting on Sulfur Group Donors
• Cysteine Synthase
• Sulfate Adenylyltransferase
• Sulfurtransferases
• thiosulfate-dithiol sulfurtransferase
• Cystathionine gamma-Lyase

Topics

• Catalysis
• Chromatography, DEAE-Cellulose
• Cystathionine gamma-Lyase (antagonists & inhibitors, metabolism)
• Cysteine Synthase (antagonists & inhibitors, metabolism)
• Enzyme Inhibitors (pharmacology)
• Oxidoreductases Acting on Sulfur Group Donors (antagonists & inhibitors, metabolism)
• Sulfate Adenylyltransferase (antagonists & inhibitors, metabolism)
• Sulfur Compounds (metabolism)
• Sulfurtransferases
• Synechococcus (drug effects, enzymology, growth & development)