Evidence of Methylobacterium spp. and Hyphomicrobium sp. in azaspiracid toxin contaminated mussel tissues and assessment of the effect of azaspiracid on their growth

A flagellar protein belonging to the genus Methylobacterium or Agrobacterium was previously observed by proteomics in azaspiracids (AZA) toxic mussels. Here, we report the isolation of two different Methylobacterium spp. (NTx1 and Tx1) from non-toxic and AZA toxic mussels, respectively, which when co-cultured with AZA exhibited significantly different growth responses - isolate Tx1 growth rate was enhanced, whereas growth of isolate NTx1 was adversely affected, compared to non-AZA supplemented control cultures. A Hyphomicrobium sp. (Tx2) also isolated from the toxic mussels achieved greater cell density in AZAs supplemented cultures.