Meeting Abstract

36.4  Wednesday, Jan. 5  Bacterial genes and larval settlement of the tube worm Hydroides elegans HUANG, Ying*; HADFIELD, Michael; University of Hawaii, Manoa yinghuan@hawaii.edu

Competent larvae of the marine tube worm Hydroides elegans can be induced to metamorphose by both single- and multi-species bacterial biofilms. In a biofilm, the marine bacterium Pseudoalteromonas luteoviolacea strongly induces metamorphosis of competent larvae of H. elegans. Using transposon mutagenesis, we identified two genes in P. luteoviolacea whose products are required for induction of metamorphosis. Subsequent research revealed that both genes lie in the same large operon, first and third in a sequence of seven open reading frames. To determine which gene in the operon is essential for metamorphic inductive capability, each gene was deleted through double recombination, and then a biofilm from each deletion-mutant strain was tested for its capacity to induce metamorphosis in competent larvae of H. elegans. The larval assays showed that the first three genes are necessary to induce the metamorphosis. These are the first identified bacterial genes that are directly involved in metamorphic in H. elegans. Further study of the products of these genes will advance understanding of the mechanisms by which biofilms influence settlement and metamorphosis of marine invertebrate larvae.