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Research was undertaken to characterize Escherichia coli isolates in interstitial water samples of a sandy beach on the southeastern shore of Lake Huron, Ontario, Canada. A survey of the beach area revealed the highest abundance of E. coli in interstitial water of the foreshore beach sand next to the swash zone. Higher concentrations of E. coli (up to 1.6 ؋ 10 6 CFU/100 ml of water) were observed in the interstitial water from the sampling holes on the beach itself compared to lake water and sediment. Repetitive extragenic palindromic PCR (REP-PCR) was used to characterize the genetic diversity of E. coli isolates from interstitial water samples on the beach. E. coli isolates from the same sampling location frequently exhibited the same REP-PCR pattern or were highly similar to each other. In contrast, E. coli isolates from different sampling locations represented populations distinct from each other. This study has identified a unique ecological niche within the foreshore area of the beach where E. coli may survive and possibly multiply outside of host organisms. The results are of interest as increasing concentrations of E. coli in recreational waters are often considered to be an indication of recent fecal pollution.

The effects of nutrient amendment and alginate encapsulation on survival of and phenanthrene mineralization by the bioluminescent Pseudomonas sp. UG14Lr in creosote-contaminated soil slurries were examined. UG14Lr was inoculated into creosote-contaminated soil slurries either as a free cell suspension or encapsulated in alginate beads prepared with montmorillonite clay and skim milk. Additional treatments were free-cell-inoculated slurries amended with sterile alginate beads, free-cell-inoculated and uninoculated slurries amended with skim milk only, and uninoculated, unamended slurries. Mineralization was determined by measuring 14CO2 released from radiolabelled phenanthrene. Survival was measured by selective plating and bioluminescence. Inclusion of skim milk was found to enhance both survival of and phenanthrene mineralization by free and encapsulated UG14Lr cells.

Roseomonas is a recently described genus of gram-negative coccobacilli formerly designated as "pink-coccoid" groups I through IV by the Centers for Disease Control and Prevention (Atlanta, Ga) because of the organism's characteristic pink colonies. Since 1991 we have isolated Roseomonas from eight patients; in seven from blood cultures and in one from a skin lesion. The seven blood isolates were from patients with clinically significant underlying diseases who had central venous catheters in place; the majority were associated with polymicrobial catheter infections. Additional characteristics of their infections are described. The eight isolates had originally been identified by us as CentersRoseomonas is a recently described genus of gram-negative coccobacilli 1 that had previously been designated as "pink-coccoid" groups I through IV 2 by the Special Bacteriology Reference Laboratory of the Centers for Disease Control and Prevention (CDC, Atlanta, Ga). On the basis of biochemical reactions and DNA relatedness of 42 pink coccoid isolates, Rihs et al 1 proposed that the genus Roseomonas should contain six new species: Roseomonas gilardii, Roseomonas cervicalis, Roseomonas fauriae, and unnamed genomospecies 4, 5, and 6. The strains they examined included 6 strains each of CDC-designated pink-coccoid groups I, II, III, and IV, along with a variety of other isolates. In this collection of 42 strains R gilardii turned out to be the most common isolate (23 of the 42). for Disease Control (CDC) pink-coccoid group III. These organisms were re-identified using the criteria of Rihs et al, and all isolates fit most closely with Roseomonas gilardii. Antibiotic profiles were fairly homogeneous showing susceptibility to many antibiotics, but uniform resistance to cefoxitin, ceftazidime, and piperacillin. Attempts to determine whether the isolates were the same strain by pulsed-field gel electrophoresis suggested that 3 of the isolates were similar. Random amplified polymorphic DNA analysis, however, demonstrated that each of the eight isolates was a unique strain.