Hydrostatic Pressure Effects on Protein Synthesis

Abstract

The effects of high hydrostatic pressure on several phases of cell-free protein synthesis have been examined. The initial rate of polyuridylic acid (poly U)-directed synthesis of polyphenylalanine showed an apparent increase at 100 atm, above which the synthetic rate was reduced sharply with increased pressure up to 640 atm where 95% inhibition was observed. The magnitude of the inhibition of polyphenylalanine synthesis with increased pressure depended strongly on the magnesium salt concentration in the reaction system. Misreading of the poly U message, as measured by insertion of leucine in place of phenylalanine, dropped rapidly with increased pressure from 1 to 350 atm, above which the amount of misreading increased. Enzymatic activation of transfer RNAs (tRNAs) was reduced by increased pressure in the range 100-640 atm, where the rate of tRNA aminoacylation was 80% inhibited. Both nonenzymatic attachment of phenylalanyl-tRNA (phe-tRNA) to the poly U-ribosome complex and stability of the phe-tRNA-poly U-ribosome complex were decreased at high pressures (100-900 atm). The results of the action of pressure on the various phases of cell-free protein synthesis suggest that the major pressure-sensitive element in the protein synthetic machinery is the ribosome.

The effect of pressure or flow stress on right ventricular protein synthesis in the face of constant and restricted coronary perfusion.

“…The data have demonstrated that a moderate pressure load in the right ventricle elicits an early increase in protein synthesis while volume loading does not, and suggest a ventricular pressure receptor affecting protein synthesis. The latter may indeed be akin to the osmotic pressure receptor postulated in the liver (32,33) or similar to the ribosome receptor suggested earlier (31). With further increases in pressure, there is an anomalous decrease in right ventricular protein synthesis.…”

“…Recently it has been demonstrated that alterations in hydrostatic pressure may affect protein synthesis, and a similar anomalous protein synthesis-pressure relationship has been described in subcellular systems (31). Progressive increases in hydrostatic pressures first increased and then decreased protein synthesis.…”

Hydrostatic pressure effects on several stages of protein synthesis in Escherichia coli

“…While this communication was being prepared, an account of studies which in part parallel our work appeared (6). Although important differences do exist, our results generally substantiate and augment these findings and have already been presented in a preliminary fashion (5).…”

“…Synthesis of Phe-tRNA was strongly inhibited by pressure: formation of this intermediate decreased rapidly, and did not occur at 800 atrn or greater. This reduction was much more pronounced than that observed by Hildebrand and Pollard (6) in a crude extract and may indicate a differential sensitivity to pressure of the aminoacyl-tRNA synthetases. Furthermore, Can.…”

“…To attain a f~~l l e r understanding of the effects of pressure on microbial activity, we have undertaken an examination of Esclzerichia coli in several ways, starting with those aspects thought to be most critical or most important. Escl~ericlzia coli was chosen for this investigation since much previous work has been carried out with this bacterium (1,3,6,7,11,12). Initial studies (I) showed that pressure reversibly inhibited cell growth and suppressed protein synthesis more than ribonucleic acid (RNA) or deoxyribonucleic acid (DNA) synthesis.…”