Some Effects of Hydrostatic Pressure on the Multiplication and Morphology of Marine Bacteria

Abstract

Hydrostatic pressure in the sea, which increases approximately 0.1 atmosphere per meter of depth, appears to be a factor that influences bacterial activities. This was indicated by the observations of Certes (1884a,b), Certes and Cochin (1884), and Regnard (1884a,b). The reports of Chlopin and Tammann (1903), Hite et al. (1914), Larson et al. (1918), and more recent ones reviewed by Macheboeuf et al. (1933), Cattell (1936), and Basset et al. (1938) indicate that the critical pressure tolerance of microorganisms ranges from 3,000 to 12,000 atmospheres, which is higher than pressures characteristic of the greatest known depth of the sea, the latter being of the order of 1,100 atmospheres. The apparent discrepancies are probably due to differences in experimental conditions, including growth phase, species, culture medium, temperature, time, and other factors now known to influence the pressure tolerance of microorganisms. ZoBell and Johnson (1949) found that many common microorganisms from surface soil and shallow water were killed in the logarithmic phase of growth in 48 hours at 30 C by pressures of only 500 to 600 atmospheres, and multiplication of some microorganisms was inhibited at 300 atmospheres. Resting cells, endospores, and bacteria from the deep sea were found to be more pressuretolerant as were organisms pressurized at higher temperatures. The term "barophilic" was coined to describe organisms that grow preferentially or exclusively at high hydrostatic pressures. Such bacteria have been found in the deep sea and also in brines from deep oil wells. Their counterparts that grow only at relatively low pressures, say up to 200 atmospheres, are described as "barophobic." Those that tolerate high pressures but grow best at normal pressures are described as "baroduric." The present paper is concerned primarily with observations on the occurrence and behavior of barophilic, barophobic, and baroduric bacteria in the sea. METHODS Bacterial cultures in the logarithmic phase of growth were transplanted to nutrient broth in small test tubes, size 10 X 50 mm, each having a sand-blasted area for numbering with a pencil. The nutrient broth used for this purpose consisted of 0.5 per cent peptone, 0.5 per cent yeast extract, and 0.01 per cent ferric phosphate in aged sea water (ZoBell, 1946). Following autoclave sterilization its reaction was pH 7.5. The medium was inoculated with enough cells to give from 100 to 1,000 per ml. The tubes were stoppered with no. 000 neoprene 1 Contribution from the Scripps Institution of Oceanography, New Series 491. This paper is a contribution from the American Petroleum Institute Research Project 43A.

An rpoE‐like locus controls outer membrane protein synthesis and growth at cold temperatures and high pressures in the deep‐sea bacterium Photobacterium sp. strain SS9

“…Barophiles are microorganisms adapted for optimal growth at hydrostatic pressures greater than one atmosphere (atm) (ZoBell and Oppenheimer, 1950) and to date all such microbes have been isolated from the deep sea, which comprises the largest portion of the biosphere (Somero, 1991). The adaptations required for barophily remain largely unknown.…”

Isolation and characterization of tyrosinase inhibitor-producing microorganisms from marine environment

“…Microorganisms from coastal seawater such as Tokyo Bay and Otsuchi Bay, and all the sediment samples were directly spread on the three media 7–9 whereas those from other off‐shore seawater samples from various depths were concentrated by a Nuclepore filter (pore size 0.2 μm; Whatman Inc., Scarborough, USA) and spread on the same media. After incubation for 1 month at 27°C, the microbial colonies that developed on the plates were isolated randomly and purified.…”

Enzymatic adaptation by bacteria under pressure

“…Care was taken to eliminate air bubbles. The culture vessels were then placed in standard pressure chambers of the type initially described by ZoBell and Oppenheimer (23). The chambers were pressurized by means of an hydraulic pump, and pressure was measured with a Heise Bourdon-tube gauge (Heise Co., Newton, Conn.).…”