Quantitative Ecology of Psychrophilic Microorganisms

Stokes, J. L; Redmond, Mary L.

doi:10.1128/aem.14.1.74-78.1966

Cited by 29 publications

(7 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Psychrophilic representatives of at least 16 genera have been reported, and the present paper describes the isolation of psychrophiles of still another genus, Bacillus. It can probably be safely predicted that further investigations will extend the list of psychrophilic genera. This large variety of psychrophilic bacteria, their ubiquity in nature, and their occurrence in many habitats in large numbers which may at times exceed those of mesophilic bacteria and frequently also thermophilic bacteria (14), strongly suggest that psychrophiles are of considerable importance in the various cycles of matter.…”

Section: Discussionmentioning

confidence: 99%

Isolation of Psychrophilic Species of Bacillus

Larkin

Stokes

1966

J Bacteriol

View full text Add to dashboard Cite

Ninety psychrophilic isolates of Bacillus were obtained from soil, mud, and water by selective enrichment at 0 C. They grew well at 0 C, optimally at 20 to 25 C, and failed to grow at 30 or 35 C. Their minimal and maximal growth temperatures were lower than those for mesophilic species of Bacillus by 10 C or more. Growth of psychrophilic isolates also occurred at-2 and-4.5 C, and both spore formation and spore germination occurred at 0 C.

show abstract

Section: Discussionmentioning

confidence: 99%

Isolation of Psychrophilic Species of Bacillus

Larkin

Stokes

1966

J Bacteriol

View full text Add to dashboard Cite

show abstract

“…The microflora on the hide or fleece will be derived mainly from soil, water and vegetation, as well as faecal material. Psychrotrophic bacteria, the group which includes potential spoilage bacteria for chilled meat, are common in soil, water and vegetation (Stokes & Redmond 1966;Druce & Thomas 1970;Warskow & Juni 1972;Jones 1973). Pseudomonas, Moraxella and Acinetobacter appear to be found more commonly than Gram positive bacteria in water and on vegetation.…”

mentioning

confidence: 99%

Sources of Psychrotrophic Bacteria on Meat at the Abattoir

Newton¹,

Harrison²,

Wauters³

1978

Journal of Applied Bacteriology

View full text Add to dashboard Cite

An export abattoir was examined to determine the sources and types of psychrotrophic bacteria which gain access to meat. Gram negative psychrotrophs were recovered from the hides, from structural and work surfaces within the abattoir, and from carcasses and meat at all stages of processing. Microbacterium thermosphactum was recovered intermittently at all sampling sites. Psychrotrophic and total counts and the incidence of M. thermosphactum on carcasses and meat increased during processing through the abattoir. Structural and work surfaces may be as important as the hide as sources of bacterial contaminants on meat. Seasonal variation was observed in psychrotrophic counts which correlated positively with rainfall and negatively with temperature.

show abstract

“…Obligately psychrophilic organisms can be readily isolated from constantly cold habitats, both marine and freshwater, although not always; no obligate psychro- philes could be isolated from constantly cold freshwater springs of southern Indiana . Facultatively psychrophilic bacteria are widespread in terrestrial and freshwater habitats (Stokes and Redmond 1966;Druce and Thomas 1970).…”

Section: Discussionmentioning

confidence: 99%

Bacterial Decomposition Processes in Lake Wingra Sediments During Winter1

Boylen

Brock

1973

Limnology & Oceanography

View full text Add to dashboard Cite

Throughout winter, viable counts of bacteria from sediments of Lake Wingra (Madison, Wisconsin) at several different incubation temperatures were always higher at 25°C than 4"C, although the temperature of the sediments remained below 4°C for over 3 months. All of the organisms isolated and initially cultivated at 4°C grew better at 25°C; no obligately psychrophilic bacteria were found. Isotope studies to measure the temperature optima of the resident bacterial flora showed that the optimunl tcmpcraturc for incorporation of 14C-glucosc into cell material and conversion of l"C-glucose into l*C-COT remained at 25°C or greater all winter. A true psychrophilic flora does not develop in these sediments in winter, and bacterial decomposition processes occur at a much slower rate in winter than in summer.Lakes in temperate climates show marked variations in temperature through the year. In Wisconsin, inland lakes are covered with ice for 3 or 4 months, and during this period temperatures of the water and sediments remain below 4°C. It was of interest to see whether bacteria in sediments became adapted to these low temperatures, since if they did, rates of bacterial metabolism might be expected to be higher than if adaptation did not occur.The fact that microorganisms are capable of adapting to low temperatures has been well documented. Obligately psychrophilic bacteria (with temperature optima below 2O'C) have been isolated from constantly cold marine environments ( Morita 1966 wide seasonal temperature variation. Temperate lake sediments constitute natural habitats where temperatures vary by the season but where the winter low of about 1°C and the summer high of 30°C remain relatively constant for several months each year. Does the microbial flora show a single optimum temperature toward either end of this temperature range or is it in a continual state of adaptation to the seasonal temperature changes in the environment? Possible answers to these questions were sought by determining temperature optima directly on the resident bacterial populations using radioisotope techniques and indirectly by culture techniques. MATERIALS AND METHODSLake Wingra is a small calcareous lake in the city of Madison, Wisconsin, at an elevation of 254 m. It is shallow, with a maximum depth of about 5 m; much of the lake was created by dredging from a marsh to provide fill for the construction of Vilas Park. We chose a single station at the southwest corner of the lake, in about 1 m of water, because it was amidst beds of water weeds which had contributed heavy organic matter to the sediments. Most of these weeds had become fragmented or decomposed before our study was made, although occasionally a fragment of plant material was present in the sample. Ice-

show abstract

Quantitative Ecology of Psychrophilic Microorganisms

Cited by 29 publications

References 8 publications

Isolation of Psychrophilic Species of Bacillus

Isolation of Psychrophilic Species of Bacillus

Sources of Psychrotrophic Bacteria on Meat at the Abattoir

Bacterial Decomposition Processes in Lake Wingra Sediments During Winter1

Contact Info

Product

Resources

About