ABSTRACT
The quantification of sub-cuticular bacteria (SCB) in echinoderms is an important step towards understanding more about this relationship. Direct counting using epifluorescence microscopy and the Limulus amoebocyte lysate (LAL) / lipopolysaccharide (LPS) assay for gram-negative bacterial endotoxin were used to enumerate SCB in ophiuroids. Both techniques have been used to distinguish species which harbour SCB and to follow the course of experiments manipulating the SCB load.
