Gramicidin S production by Bacillus brevis in simulated microgravity

Fang, A.; Pierson, D. L.; Mishra, S. K.; Koenig, D. W.; Demain, A. L.

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NASA NTRS · 20040172998

Gramicidin S production by Bacillus brevis in simulated microgravity

Fang, A.·Pierson, D. L.·Mishra, S. K.·Koenig, D. W.·Demain, A. L.

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Abstract

In a continuing study of microbial secondary metabolism in simulated microgravity, we have examined gramicidin S (GS) production by Bacillus brevis strain Nagano in NASA High Aspect Rotating Vessels (HARVs), which are designed to simulate some aspects of microgravity. Growth and GS production were found to occur under simulated microgravity. When performance under simulated microgravity was compared with that under normal gravity conditions in the bioreactors, GS production was found to be unaffected by simulated microgravity. The repressive effect of glycerol in flask fermentations was not observed in the HARV. Thus the negative effect of glycerol on specific GS formation is dependent on shear and/or vessel geometry, not gravity.

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NASA Discipline Number 04-10 NASA Discipline Environmental Health NASA Program Environmental Health NASA Center JSC Gravity, Altered/adverse effects Gramicidin/biosynthesis Bacillus/growth & development/metabolism Antibiotics, Peptide/biosynthesis United States Glycerol/pharmacology Support, U.S. Gov't, Non-P.H.S Bioreactors Space Simulation Fermentation United States National Aeronautics and Space Administration Fructose/pharmacology Comparative Study Inositol/pharmacology

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Fang, A., Pierson, D. L., Mishra, S. K., Koenig, D. W., Demain, A. L.. 1997-04-01. Gramicidin S production by Bacillus brevis in simulated microgravity. https://ntrs.nasa.gov/citations/20040172998

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