BLOOMS OF SEQUENCE-SPECIFIC CULTURABLE BACTERIA IN THE SEA

Using specific deoxyoligonucleotide probes we have discovered seasonal ly strong (up to almost-equal-to 100%) dominance of bacteria hybridizi ng to a single probe, in near shore waters off Scripps pier (32-degree s 53' N; 117-degrees 15' W). The probes were designed from partially s equenced 16S rRNA (V3 domain) of isolated marine bacteria. The results indicate that this approach may be used for studies of bacterial popu lations in the marine environment. We have shown that a number of geno types that at times are dominant in the natural assemblages are cultur able (and not, ''viable-but-unculturable'). Additionally, our data sug gests that the discrepancy between viable counts and direct counts in sea water samples can be explained by low plating efficiency.