Synthesis of protein and ribonucleic acid in a psychrophile at normal and restrictive growth temperatures.
A defined medium was capable of supporting the growth of a psychrophilic coccus over its growth temperature range, -4 to 25 C. A rapid loss of viability occurred when exponential cells were transferred to growth-restricting temperatures above 25 C. Comparative studies of the chemistry of exponential-phase cells and cells exposed to supermaximum temperature indicated that this loss of viability is not due to temperature-induced membrane damage, inhibition of respiration or energy metabolism, or depletion of intracellular reserves. Moribund and dead cell populations showed an elevated level of intracellular adenosine-5'-triphosphate and amino acids-a finding reflected in the reduced rate of amino acid synthesis during the recovery of heat-shocked cells-and also leakage of degraded ribonucleic acid products into the medium. Incorporation studies indicated that loss of viability at 30 C was correlated with inhibition of protein synthesis, followed later by inhibition of ribonucleic acid synthesis. Deoxyribonucleic acid synthesis was unaffected by temperature above the maximum.
D000085:Acetates / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002247:Carbon Isotopes; D002463:Cell Membrane Permeability; D004269:DNA, Bacterial / Q000378:metabolism; D005827:Genetics, Microbial; D006836:Hydro-Lyases / Q000378:metabolism; D008190:Lyases / Q000378:metabolism; D008837:Micrococcus / Q000201:enzymology / Q000378:metabolism*; D009711:Nucleotides / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism; D010101:Oxygen Consumption; D010649:Phenylalanine / Q000378:metabolism; D012329:RNA, Bacterial / Q000096:biosynthesis* / Q000378:metabolism; D013696:Temperature; D013936:Thymidine / Q000378:metabolism; D000637:Transaminases / Q000378:metabolism; D014498:Uracil / Q000378:metabolism
D000085:Acetates; D000596:Amino Acids; D001426:Bacterial Proteins; D002247:Carbon Isotopes; D004269:DNA, Bacterial; D009711:Nucleotides; D012329:RNA, Bacterial; D010649:Phenylalanine; D014498:Uracil; D000255:Adenosine Triphosphate; D010088:Oxidoreductases; D000637:Transaminases; D008190:Lyases; D006836:Hydro-Lyases; D013936:Thymidine