Efficiencies of Recovery of Bdellovibrios from Brackish- Water Environments by Using Various Bacterial Species as Prey

Abstract

A total of 44 bacterial species subdivided into 10 trial experiments have been used as prey for the recovery of bdellovibrios from samples of water from a brackish tidal pond and an aquarium saltwater tank. In an initial investigation, the recovery efficiency of each of the test bacterial species was compared with that of a designated standard prey, Vibrio parahaemolyticus P-S. The results revealed that in each case strain P-5 yielded an equal or significantly greater number of plaques of bdellovibrios than the test prey with but a single exception, strain CS5. In repeat experiments, CS5 yielded fewer plaques than P-5. To determine whether the use of multiple bacterial species compared with a single species as prey would increase the number of PFU of bdellovibrios recovered, material from plaques appearing on each of the test prey in the respective trials was sequentially subcultured onto two respective agar plates, the first containing as prey V. parahaemolyticus P-5 and the second containing the initial test organism. In nearly every case, subculture of plaques from lawns of the test prey to P-5 resulted in plaque formation. On the basis of the results, the use of several test prey and P-5 did not result in the recovery of any more bdellovibrio PFU than the use of P-5 alone. In this study, V. parahaemolyticus P-S was observed to be the most efficient prey for the recovery of bdellovibrios from moderate salt water.

ISOLATION OF BDELLOVIBRIOS THAT PREY ON ESCHERICHIA COLI O157:H7 AND SALMONELLA SPECIES AND APPLICATION FOR REMOVAL OF PREY FROM STAINLESS STEEL SURFACES1

“…Bdellovibrio strains show prey specificity among various genera and species of gram-negative bacteria. Although, enteric bacteria are suitable target organisms, many bdellovibrios may not efficiently attack and lyse different bacterial species and serotypes (Fratamico and Whiting 1995;Schoeffield and Williams 1990;Starr and Stolp 1976). Bdellovibrio strains isolated from marine habitats require sodium chloride or sea water for growth.…”

“…Bdellovibrios are capable of infecting and eventually causing lysis of a wide variety of gram-negative bacteria; however, the prey range susceptible to specific Bdellovibrio strains varies (Fratamico and Whiting 1995;Schoeffield and Williams 1990;Starr and Stolp 1976;Scherff 1973). Previous studies showed that the prey range of B. bacreriovorus 109J did not include E. cofi 0157:H7 and most Salmonella species tested in a two-membered system (Fratamico and Whiting 1995).…”

“…Bdellovibrio isolate 45k reduced apopulation of E. coli dried on stainless steel su#aces by 3.6 log,, CFIJ/cmz following 24 h contact time and at a 10:l predator to prey ratio and was also effective in reducing the level of biojilm cells.Bdellovibnos can potentially be utilized for removal of bacteria from suqaces of food processing equipment and possibly for controlling the growth ofpathogenic and spoilage bacteria in foods. (Richardson 1990;Fry and Staples 1976;Klein and Casida 1967;Schoeffield and Williams 1990) and from other aquatic habitats including shellfish (Kelley and Williams 1992;Williams et al 1995b). Williams et aL(1995a;1995b) found bdellovibrios associated with surfaces submerged in natural waters and on which ' Mention of brand or firm names does not constitute an endorsement by the U.S. Department of Agriculture over others of a similar nature not mentioned.…”

Isolation and Classification of Bdellovibrio and Like Organisms

“…SWYE plates (see recipe) Vibrio parahaemolyticus P-5 (Shoeffield and Williams, 1990) Sterile ocean water (see recipe) Polypeptone 20 (Pp) medium (see recipe) Pp top agar, molten (see recipe) Pp plates (see recipe) 28 • and 25 • C incubators Cell spreader, sterile 1. To SWYE plates, add 100 μl V. parahaemolyticus P-5 and spread evenly to distribute.…”

Prey range and genome evolution ofHalobacteriovorax marinuspredatory bacteria from an estuary

“…How Halobacteriovorax shapes saltwater microbial communities depends in part on which bacterial species are susceptible to predation by different Halobacteriovorax strains. Tests of Halobacteriovorax isolates from various saltwater environments indicate that, in general, this genus has a broad prey range [12, 13]. For example, predatory bacteria in saltwater aquarium and tidal pool samples attacked a phylogenetically diverse set of prey, including multiple species of Vibrio , Pseudomonas and E. coli [13].…”