title: Effect of simulated microgravity on E. coli K12 MG1655 growth and gene expression.
abstract: This study demonstrates the effects of simulated microgravity on E. coli K 12 MG1655 grown on LB medium supplemented with glycerol. Global gene expression analysis indicated that the expressions of hundred genes were significantly altered in simulated microgravity conditions compared to that of normal gravity conditions. Under these conditions genes coding for adaptation to stress are up regulated (sufE and ssrA) and simultaneously genes coding for membrane transporters (ompC, exbB, actP, mgtA, cysW and nikB) and carbohydrate catabolic processes (ldcC, ptsA, rhaD and rhaS) are down regulated. The enhanced growth in simulated gravity conditions may be because of the adequate supply of energy/reducing equivalents and up regulation of genes involved in DNA replication (srmB) and repression of the genes encoding for nucleoside metabolism (dfp, pyrD and spoT). In addition, E. coli cultured in LB medium supplemented with glycerol (so as to protect the cells from freezing temperatures) do not exhibit multiple stress responses that are normally observed when cells are exposed to microgravity in LB medium without glycerol.
authors.affiliation: Centre for Cellular and Molecular Biology, Hyderabad, India.
authors.forename: Kotakonda
authors.initials: K
authors.lastname: Arunasri
authors.forename: Mohammed
authors.initials: M
authors.lastname: Adil
authors.forename: Katari
authors.initials: K
authors.lastname: Venu Charan
authors.forename: Chatterjee
authors.initials: C
authors.lastname: Suvro
authors.forename: Seerapu
authors.initials: S
authors.lastname: Himabindu Reddy
authors.forename: Sisinthy
authors.initials: S
authors.lastname: Shivaji
mesh_terms: D003470:Culture Media; D048168:Escherichia coli K12 / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005990:Glycerol; D020411:Oligonucleotide Array Sequence Analysis; D013312:Stress, Physiological; D018474:Weightlessness Simulation
chemical_list: D003470:Culture Media; D029968:Escherichia coli Proteins; D005990:Glycerol