Auxotrophic mutant of the cyanobacterium Nostoc muscorum showing absolute requirement of Cs+ or Rb+ for diazotrophy and autotrophy

✍ Scribed by Santosh Bhargava; Rajendra Chauhan; Pramod K. Patil; Sarva Daman Singh

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 80 KB
• Volume: 46
• Category: Article
• ISSN: 0233-111X
• DOI: 10.1002/jobm.200510075

✦ Synopsis

Abstract

Caesium‐resistant (Cs^+^‐R) mutant clones of the cyanobacterium Nostoc muscorum were characterized for diazotrophic growth in a medium devoid of Cs^+^ or Rb^+^ or both. Cs^+^‐R phenotype suffered severe genetic damage of a pleiotropic nature affecting diazotrophic growth, chlorophyll a content, nitrogenase activity and photosynthetic O~2~ evolution. Mutation leading to development of Cs^+^‐R phenotype could be overcome by availability of Cs^+^/Rb^+^. Parent and mutant strains were similar with respect to their Cs^+^/Rb^+^ uptake. Available data suggests operation of an efficient coupling of the two incompatible reactions viz. oxygenic photosynthesis and oxygen sensitive N~2~ fixation in this cyanobacterium. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)