Accession Number:

ADA268276

Title:

Analysis of Toxic and Non-Toxic Alexandrium (Dinophyceae) Species Using Ribosomal RNA Gene Sequences

Descriptive Note:

Doctoral thesis

Corporate Author:

WOODS HOLE OCEANOGRAPHIC INSTITUTION MA

Personal Author(s):

Report Date:

1993-02-01

Pagination or Media Count:

267.0

Abstract:

Sequences of small subunit Ss and large subunit Ls ribosomal RNA genes rDNA from the marine dinoflagellates Alexandrium tamarense, A. catenella, A. fundyense, A. affine, A. minutum, A. lusitanicum and A. andersoni were compared to assess the organisms relationships. Cultures represent isolates from North America, Western Europe, Thailand, Japan, Australia and the ballast water of several cargo vessels, and include both toxic and non-toxic strains. An emphasis was placed on the A. tamarensecatenellafundyense species complex, a group of morphotypically-similar organisms found in many regions of the world. Two distinct SsrRNA genes, termed the A gene and the B gene, were found in a toxic A. fundyense isolated from eastern North America. The B gene is considered to be a pseudogene. A restriction fragment length polymorphism RFLP assay developed to detect the A and B genes revealed five distinct groups of Alexandrium isolates. Three subdivide the A. tamarensecatenellafundyense complex, but do not correlate with morphospecies designations. The two remaining groups are associated with cultures that clearly differ morphologically from the A. tamarense catenellafundyense group the fourth group consists of A. affine isolates, and the fifth group is represented by A. minutum, A. lusitanigum and A. andersoni.

Subject Categories:

  • Biology
  • Toxicology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE