title: Lipolytic bacteria in the Ottawa river.
abstract: Lipolytic bacteria were isolated from two stations on Brewery Creek, an arm of the Ottawa River, during the winter of 1971-72. Total counts were approximately sevenfold higher at the more polluted downstream station, whereas lipolytic counts were about 100-fold higher. At this station, significantly more lipolytic bacteria grew on plates incubated at 20 C than at 4 C, suggesting that the population was comprised of both mesophiles and psychrophiles. However, at the upstream station, approximately the same number were obtained at both temperatures. A total of 434 isolates, mainly from the downstream station, were tentatively classified. The major groups were Pseudomonas, Acinetobacter-Moraxella, and Aeromonas. Though the total number of lipolytic bacteria was fairly constant throughout the winter, the relative abundance of the acinetobacters dropped from approximately 90% in November to less than 10% in March, and then increased. The aeromonads and pseudomonads showed the opposite trend. Most of the bacteria, though isolated at 4 C, also grew at 30 C. Lipolysis, however, was generally strongest at 20 C or below.
mesh_terms: D000333:Aeromonas / Q000302:isolation & purification; D000421:Alcaligenes / Q000302:isolation & purification; D001419:Bacteria / Q000302:isolation & purification*; D002170:Canada; D002374:Catalase; D003470:Culture Media; D004755:Enterobacteriaceae / Q000302:isolation & purification; D005374:Filtration; D005780:Gelatin / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006868:Hydrolysis; D050356:Lipid Metabolism; D008566:Membranes; D009016:Moraxella / Q000302:isolation & purification; D010088:Oxidoreductases; D011549:Pseudomonas / Q000302:isolation & purification; D013291:Streptococcus / Q000302:isolation & purification; D013997:Time Factors; D014733:Vibrio / Q000302:isolation & purification; D014871:Water Microbiology; D014876:Water Pollution
chemical_list: D003470:Culture Media; D005780:Gelatin; D010088:Oxidoreductases; D002374:Catalase; D005947:Glucose