pseudoalteromonas piscicida pseudoalteromonas piscicida pseudoalteromonas piscicida is a marine bacterium. it is known to produce a quorum sensing molecule called 2-heptyl-4-quinolone (hhq), which functions as a bacterial infochemical. research into the effects of this infochemical on phytoplankton is currently being conducted by dr. kristen whalen of haverford college. pseudoalteromonas piscicida scientific classification domain: bacteria phylum: pseudomonadota class: gammaproteobacteria order: alteromonadales family: pseudoalteromonadaceae genus: pseudoalteromonas binomial name pseudoalteromonas piscicida(ex bein 1954) gauthier et al. 1995 synonyms flavobacterium piscicida bein 1954 pseudomonas piscicida (bein 1954) buck et al. 1963