Comparative studies on the in Vitro response of bacteria to invertebrate body fluids. I. Dendrostomum zostericolum, a sipunculid worm

Abstract

Six species of marine bacteria, five gram-negative rods and one gram-positive micrococcus, plus a strain of the terrestrial gram-negative rod Serratia marcescens, were tested. They were incubated in vitro in cell-free coelomic fluid and whole coelomic fluid from the sipunculid worm Dendrostomum zostericolum. Incubation with seawater alone and in a mixture of seawater and bovine albumin were used as controls. The whole fluid was strongly depressive or fatal to all the bacteria except the grampositive micrococcus and S. marcescens. Cell-free fluid was less depressive or fatal in its effects. There is discussion of the possibility that some of the depressive effects of the sipunculid fluids might be similar to the effect of incubation in seawater alone. Attributes of the various bacteria that might make them susceptible or resistant to the effects of the fluids are discussed also.