L F Hanne

Characterization of JP-7 jet fuel degradation by the bacterium Nocardioides luteus strain BAFB

In the fall of 1996, numerous bacteria capable of degrading JP‐7 jet fuel were isolated from soil collected at Beale Air Force Base in northern California. The most prevalent organism, identified as Nocardioides luteus by16s rRNA sequencing (MIDI Labs, Inc.), was selected for further analysis. Analysis of JP‐7 following inoculation with N. luteus demonstrated degradation of the C11 alkane component of the fuel. Growth rates of N. luteus were determined with alkanes of various lengths as the sole carbon and energy source. The organism grew best on shorter length alkanes (C8 and C10). Growth was measurably slower on C11, and minimal on C12, C13, and C14.

Impact of Salmon Spawning on Microbial Communities in a Northern California River

ABSTRACT We studied microbial communities in the water column during the fall 2002 Chinook salmon (Oncorhynchus tshawytscha) run on the Feather River in northern California. We quantified culturable heterotrophic bacteria, live/dead bacteria, and Aeromonas spp. bacteria in the water column. Concentrations of each group peaked two weeks following the peak of new salmon carcasses in the river then declined. During the fall 2003 Chinook salmon spawning season we used fluorescent in situ hybridization with domain-specific DNA probes to characterize changes in epilithic biofilm communities. Eukarya counts were lower than Bacteria counts earlier in the salmon run; however, by the end of the salmon migration season, cell concentrations of Bacteria and Eukarya were approximately equal. Chlorophyll a concentrations from epilithic biofilm began to increase in parallel with the increase in Eukarya. Since the biofilms persisted through the spawning season, it is possible that these communities support a food chain that leads to insect populations which become nutrients for the newly hatched salmon fry in the winter and spring.

Hemagglutinins (Colonization Factors?) Produced by Vibrio Cholerae

Although cholera is the prototype of the enterotoxic enteropathies in which the etiologic agents (after passing the gastric barrier) adhere to and colonize the epithelial surface of the small bowel (and there liberate their enterotoxin), relatively little is known about the mechanism(s) of attachment., Suggestive evidence that Vibrio cholerae have fimbriae (pili) was presented in 1968 (21), but this isolated report has not been substantiated by subsequent investigations. Observations in our laboratory (6, 16, 17) provided no support for the participation of surface organelles in adherence; rather, the evidence suggested that adherence was the result of a more direct interaction between the surface coat of the vibrios and the tips of the microvilli of the host intestinal epithelial cells.