Introduction The purpose of many ecological studies is to identify interactions between faunistic ecosystem components by means of laboratory and field experiments. It has often been shown that abiotic and biotic factors such as competition, disturbance and predation influence the composition and dynamics of macrobenthos communities (REISE, 1977; COMMITO and AMBROSE, 1985; AMBROSE, 1986; BEUKEM...

There is increasing concern about the toxicities and potential risks, both still poorly understood, of silver nanoparticles for the aquatic environment after their eventual release via wastewater discharges. In this study, the toxicities of sediment associated nano (<100 nm)-, micron (2–3.5 μm)and ionic (AgNO3)-Ag on the sediment-dwelling polychaete, Nereis diversicolor, were compared after 10 ...

Abalone sperm use lysin to make a hole in the egg's protective vitelline envelope (VE). When released from sperm, lysin first binds to the VE receptor for lysin (VERL) then dissolves the VE by a non-enzymatic mechanism. The structures of the monomeric and dimeric forms of Haliotis rufescens (red abalone) lysin, previously solved at 1.90 and 2.75 A, respectively, have now been refined to 1.35 an...

Settlement and metamorphosis of marine invertebrate larvae is an ecological process of profound importance to the structure of benthic marine communities. Yet, metamorphosis is also a developmental process and our understanding of the mechanisms that regulate it remains relatively poor. Over the last 15 years, a nitric oxide (NO) based signaling system has emerged as the most phylogenetically w...

Muscles of invertebrate species contain abundant quantities of soluble, sarcoplasmic, high affinity Ca2+-binding proteins (SCBPs). The SCBPs belong to the calmodulin superfamily and contain four homologous domains (I-IV) which arose by reduplication of a gene for a small ancestral protein. We have determined the amino acid sequence of the SCBP from the sandworm Nereis diversicolor. This protein...

Red and brown seaweeds are natural foods for Haliotis discus hannai, an abalone species with dark-brown shells that is also known as Ezo. This preliminary study investigated the effect of seaweed on the color and quality of the meat and shells of this abalone. Results showed that a formulated test diet and an established commercial feed individually resulted in lower growth rates and meat prote...

Chemical communication between sperm and egg is a critical factor mediating sexual reproduction. Sperm attractants may be significant evolutionarily for maintaining species barriers, and important ecologically for increasing gamete encounters. Still unresolved, however, are the functional consequences of these dissolved signal molecules. Here, we provide experimental evidence that sperm chemoat...