≤1,200 nmol [SO4]2-/cm^3 sponge/day
||Cold-water sponge Geodia barretti
||Taylor MW, Radax R, Steger D, Wagner M. Sponge-associated microorganisms: evolution, ecology, and biotechnological potential. Microbiol Mol Biol Rev. 2007 Jun71(2):295-347. DOI: 10.1128/MMBR.00040-06 p.323 left column 2nd paragraphPubMed ID17554047
|| Hoffmann, F. et al., 2005. An anaerobic world in sponges. Geomicrobiol. J. 22:1-10. link abstract
||P.323 left column 2nd paragraph: "In G. barretti, FISH [Fluorescence in situ hybridization] detection of sulfate reducers belonging to members of the genera Desulfoarculus, Desulfomonile, and/or Syntrophus (estimated abundance, 1.8% of the total bacterial community) was complemented by isotopic measurements of sulfate reduction rates and analysis of oxygen profiles within the sponge (primary source). Sulfate reduction is an anaerobic process, and through the use of microelectrodes (ref 354), these authors were able to demonstrate the presence of anoxic zones within the sponge, particularly during periods of pumping inactivity (primary source). The estimated sulfate reduction rates in G. barretti, of up to 1,200 nmol [SO4]2− cm^3 sponge day^−1, are among the highest recorded in natural systems." Primary source abstract: "Associated microorganisms have been described in numerous marine sponges. Their metabolic activity, however, has not yet been investigated in situ. [Investigators] quantified for the first time microbial processes in a living sponge. Sulfate reduction rates of up to 1200 nmol/cm^3/day were measured in the cold-water bacteriosponge Geodia barretti."