|Title||Genotypic diversity within a natural coastal bacterioplankton population.|
|Publication Type||Journal Article|
|Year of Publication||2005|
|Authors||Thompson JR, Pacocha S, Pharino C, Klepac-Ceraj V, Hunt DE, Benoit J, Sarma-Rupavtarm R, Distel DL, Polz MF|
|Date Published||2005 Feb 25|
|Keywords||Alleles, Chaperonin 60, Ecosystem, Electrophoresis, Gel, Pulsed-Field, Genetic Variation, Genome, Bacterial, Genotype, Molecular Sequence Data, Plankton, Polymerase Chain Reaction, Ribotyping, Seawater, Time Factors, Vibrio|
The genomic diversity and relative importance of distinct genotypes within natural bacterial populations have remained largely unknown. Here, we analyze the diversity and annual dynamics of a group of coastal bacterioplankton (greater than 99% 16S ribosomal RNA identity to Vibrio splendidus). We show that this group consists of at least a thousand distinct genotypes, each occurring at extremely low environmental concentrations (on average less than one cell per milliliter). Overall, the genomes show extensive allelic diversity and size variation. Individual genotypes rarely recurred in samples, and allelic distribution did not show spatial or temporal substructure. Ecological considerations suggest that much genotypic and possibly phenotypic variation within natural populations should be considered neutral.