MICROBIAL ECOLOGY OF ACTIVATED SLUDGE. II. BACTERIOPHAGES, BDELLOVIBRIO, COLIFORMS, AND OTHER ORGANISMS.
A comparative estimation of the coliform population of raw sewage, activated sludge, and the effluent derived therefrom revealed that raw sewage had a preponderance of Escherichia coli (75%), as compared with 25 and 30%, respectively, in sludge and effluent. Nitrogen-free mannitol-sucrose enrichments of activated sludge resulted in the isolation of Azotobacter agilis, Aerobacter aerogenes, Corynebacterium laevaniformans, and an Achromabacter species. Sludge had a large population of C. laevaniformans and A. aerogenes but not of Azotobacter. The bacterial parasites, Bdellovibrio and bacteriophages, were not active during activated-sludge treatment. A 10-fold reduction in phage content occurred after 2 hr of aeration, but the Bdellovibrio population was unaffected.
D042402:Achromobacter; D001395:Azotobacter; D001435:Bacteriophages; D001501:Bdellovibrio; D003352:Corynebacterium; D003470:Culture Media; D004463:Ecology; D021902:Enterobacter aerogenes; D004926:Escherichia coli; D009584:Nitrogen; D012106:Research; D012722:Sewage
D003470:Culture Media; D012722:Sewage; D009584:Nitrogen
ACHROMOBACTER; AEROBACTER AEROGENES; AZOTOBACTER; BACTERIOPHAGE; CORYNEBACTERIUM; CULTURE MEDIA; ECOLOGY; ESCHERICHIA COLI; EXPERIMENTAL LAB STUDY; SEWAGE