Mutational Engineering of the cyanobacterium Nostoc muscorum for resistance to growth-inhibitory action of LiCl and NaCl

Current Microbiology
Santosh BhargavaPrakash S Bisen

Abstract

The effect of NaCl on two vital processes of cyanobacterial metabolism, viz. N(2) fixation and oxygenic photosynthesis, was studied in the cyanobacterium Nostoc muscorum grown diazotrophically. An increase in NaCl concentration suppressed the formation of heterocyst and adversely affected the nitrogenase activity in the parent, whereas in Li(+)-R and Na(+)-R mutants NaCl stress did not cause any adverse effect. The rate of photosynthetic O(2)-evolution was also adversely affected by the NaCl stress, but the magnitude was less than that of nitrogenase activity. L-Proline, the well-known osmoprotectant, provided protection to the cyanobacterium against NaCl stress. The parent strain utilized L-proline as a nitrogen source and suppressed heterocyst formation and nitrogenase activity, while mutants showed normal heterocyst frequency and nitrogenase activity. Therefore, it may be that the proline metabolism is altered as a result of mutation. The intracellular levels of proline in the parent were enhanced about threefold in the medium containing 1 mol x m(-3) proline, while in mutants there was no significant increase in the intracellular level of proline. In the medium containing both NaCl and proline, the intracellular level of pr...Continue Reading

Citations

Feb 10, 2006·FEMS Microbiology Ecology·Malin NilssonBirgitta Bergman
Jul 25, 2020·Desalination·Endalkachew Sahle-DemessieAmro El Badawy
Mar 13, 2014·Plant Physiology·Jaime M AmezagaMichael R Templeton
Jun 14, 2021·Bioresource Technology·Anil Kumar PatelCheng Di Dong

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antimicrobial Resistance (ASM)

Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections.

Antimicrobial Resistance

Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections.