FILAMENT FORMATION BY ESCHERICHIA COLI AT INCREASED HYDROSTATIC PRESSURES

Abstract

ZO)BELL, (CLA-UDE E. (University of California, La Jolla), AND ANDRE B. COBET. Filament formIa-tioIn by Escherichia coli at increased hydrostatic pressures. J. Bacteriol. 87:710-719. 1964.-The repiroduction ais well as the growth of Escher-ichia coli is retarded by hydrostatic pressures ranging froii 200 to 500 atm. Reproduction was indicated by an increase in the nunmber of cells deternmined by plating on EMIB Agar as well as by direct microscopic counts. (Growth, whiCh is not necessarily synonymnouls with reproduction, was indicated by increase in dry weight, and protein content of the bacterial bioimass. At incretased pressures, cells of thiree different strains of E. coli tended to form long filaiments. Whereas Imlost normal cells of E. coli that developed at 1 atim were only about 2 A long, the imiean length of those that, dleveloped at 475 atml was 2.93 u for strain R4 3.99 , for strain 5, and 5.82 , for strain B cells. Nearly 90e/, of the bac

High pressure conditions stimulate expression of chloramphenicol acetyltransferase regulated by thelacpromoter inEscherichia coli

“…The E. coli JM109 cells were able to divide under a pressure of 30 MPa with a doubling time of around 1.08 h, as compared with 0.86 h at atmospheric pressure (0.1 MPa). When E. coli ceils were incubated at 50 MPa the increase in optical density at 660 nm was due to cell elongation, and not cell division [16]. Because 50 MPa caused severe inhibition of cell growth and was likely to change levels of gene expression as an indirect result of this pronounced effect, we decided to When E. coli JM109 carrying plasmid was cultivated at high pressure, the copy number of the plasmid per cell showed a tendency to increase.…”

The combined action of carvacrol and high hydrostatic pressure on Listeria monocytogenes Scott A

“…The HHP treatment of microorganisms leads to a number of changes in the cell. Pressures in the range of 20±50 MPa inhibit cell division more than cell growth, causing single cells to form long ®laments (Zobell et al 1963). Pressure affects motility (Kitching 1957) and, in Escherichia coli, it was demonstrated that DNA synthesis stops at around 50 MPa, protein synthesis around 58 MPa and RNA synthesis around 77 MPa (Yayanos and Pollard 1969).…”

Effects of ethanol on the growth and elongation of Escherichia coli under high pressures up to 40 MPa

“…We have reported the antagonistic effect of pressure on the anesthetic actions of alcohols using model membranes [4][5][6] and its application to the fermentation of glucose to alcohol by yeast [7]. It is known that E. coli cells often elongate when cultured under high pressure [8] or in medium containing toxic compounds. However, the combined effects of lower pressure and toxic compounds such as ethanol have not been investigated from the view point of pressure reversal 322 of anesthesia.…”