Bacteria associated with crabs from cold waters with emphasis on the occurrence of potential human pathogens

Abstract

A diverse array of bacterial species, including several potential human pathogens, was isolated from edible crabs collected in cold waters. Crabs collected near Kodiak Island, Alaska, contained higher levels of bacteria than crabs collected away from regions of human habitation. The bacteria associated with the crabs collected near Kodiak included Yersinia enterocolitica, Klebsiella pneumoniae, and coagulasenegative Staphylococcus species; the pathogenicity of these isolates was demonstrated in mice. Although coliforms were not found, the bacterial species associated with the tissues of crabs collected near Kodiak indicate possible fecal contamination that may have occurred through contact with sewage. Compared with surrounding waters and sediments, the crab tissues contained much higher proportions of gram-positive cocci. As revealed by indirect plate counts and direct scanning electron microscopic observations, muscle and hemolymph tissues contained much lower levels of bacteria than shell and gill tissues. After the death of a crab, however, the numbers of bacteria associated with hemolymph and muscle tissues increased significantly. Microcosm studies showed that certain bacterial populations, e.g., Vibrio cholerae, can be bioaccumulated in crab gill tissues. The results of this study indicate the need for careful review of waste disposal practices where edible crabs may be contaminated with microorganisms that are potential human pathogens and the need for surveillance of shellfish for pathogenic microorganisms that naturally occur in marine ecosystems.

Haem utilization in Vibrio cholerae involves multiple TonB‐dependent haem receptors

“…Haemoglobins derived from marine organisms may be another source of haem-iron for V. cholerae. Studies have shown that a variety of filter-feeding marine organisms accumulate V. cholerae to high levels when exposed to sea water containing V. cholerae (Faghri et al, 1984;Murphree and Tamplin, 1995). The persistence of V. cholerae within these hosts may be determined by the availability of nutrients such as iron.…”

AEROMONAS HYDROPHILA and AEROMONAS SOBRIA AS POTENTIAL FOOD POISONING SPECIES: A REVIEW1

“…Aeromonas species have been reported in both untreated and chlorinated drinking water (LeChevallier et al 1980(LeChevallier et al ,1982Burke et al 1984b. The organism is commonly isolated from fish (Boulanger et al 1977) and shellfish (Konuma et al Faghri et al 1984). Incidences of human Aeromonas gastroenteritis have been attributed t o both contaminated water (Davis et al 1978;Kipperman et al 1984) and fish (Kalina 1977).…”

Microorganisms on Commercially Processed Alaskan Finfish

“…Commerce, 1990). Microbial studies conducted on Alaskan seafoods have included: salmon (Snow and Beard, 1939;Elliot, 1987a), pollock surimi (Elliot, 1986(Elliot, , 1987bHimelbloom et al, 1991a,b), native seafoods (Zottola et al, 1983), and shellfish (Faghri et al, 1984;Kaysner, 1981;Vasconcelos et al, 1975). Microbiological data are essential for evaluating seafood quality and for developing seafood processing guidelines.…”