“From individuals to ecosystems: the importance of subcellular metal distributions to toxicity and trophic transfer in metal-impacted marine benthic communities”

The subcellular metal distribution of soft-bodied invertebrates (clams, shrimp, worms) has been studied extensively, and linkages between inappropriate internal binding (i.e., to enzymes and organelles) and toxicity are well established. In some cases, however, internal sequestration of metals via metal-binding proteins and/or metal-rich concretions (both involved in detoxification) may confer increased tolerance or resistance. Prof. Wallace has demonstrated that the subcellular storage of metal within prey plays a key role in controlling metal trophic transfer: metals bound to proteins and organelles are highly available to predators upon ingestion, whereas metals stored in concretions have much reduced availability.

Because subcellular metal storage can be species- and population-dependent, the composition of metal-impacted benthic communities may influence the bioavailability and trophic transfer of metals to predators. Communities dominated by species or populations relying on detoxification via metal-binding proteins may enhance trophic transfer, while those storing metals primarily in metal-rich concretions (similar to kidney stones) may reduce food-chain transfer. These metal-handling strategies have consequences at both the individual level (tolerance vs toxicity, altered metabolism, behavior, and growth) and the population level (persistence, reduced abundance, or absence from impacted environments).

As a result, community composition of marine benthic systems—shaped by species- and population-specific metal-handling strategies—has the potential to influence ecosystems by controlling metal trophic transfer from prey to predator. Although prey-dependent processes are central to this control, predator-dependent factors such as digestive strategies may also contribute. Professor Wallace and the Wallace Research Group have explored the ecological importance of subcellular metal distribution and trophic transfer since ~1999. This talk will review these studies, along with related work by other researchers who have applied the methods and approaches developed by Professor Wallace and his students.

~ THIS IS A CLUE EVENT