Bacterial communities associated with tail fan necrosis in spiny lobster, Jasus edwardsii

Spiny lobsters are among the most valuable seafood products, but their commercial value is greatly diminished by tail fan necrosis (TFN), an unsightly blackening and erosion of the posterior margins on the abdomen. The condition results from bacterial incursion following physical damage to the cuticle. In this current study, the bacterial communities on the cuticle of tail fans of wild spiny lobsters with and without TFN were examined using 16S rDNA Illumina sequencing to identify whether there is a group of bacteria associated with TFN. The bacterial communities in the affected cuticle had significantly less richness, diversity and evenness, but greater variability between samples than those in unaffected cuticle. There were 21 phylotypes closely associated with TFN, of which, those belonging to Aquimarina, Flavobacterium, Neptunomonas, Streptomyces, Flavobacteriaceae and Thiohalorhabdales were most important. The affected cuticle samples were clustered into two microbial colonization states, each characterized by distinct phylotypes that are closely associated with TFN, suggesting different phylotypes were associated with different microbial colonization states of TFN. These bacteria appear to develop their association through opportunistic pathways created by the provision of changes in the bacterial habitat associated with injury to the cuticle or compromised immunity subsequent to the injury.