Dimethylsulfoniopropionate
From Biocrawler, the free encyclopedia.
Dimethylsulfoniopropionate ((CH3 )2S+CH2CH2COO−; more frequently abbreviated to DMSP), is a metabolite found in marine phytoplankton and some species of terrestrial plants. Although originally considered to act only as an osmolyte, several other physiological and environmental roles have also been discovered.
DMSP is broken down by marine microbes to form two major volatile sulfur products, each with distinct effects on the environment. It's major breakdown product is methanethiol (CH3SH) which is assimilated by bacteria into protein sulfur.
Its second volatile breakdown product is dimethylsulfide (CH3SCH3; DMS). Most DMS in seawater is cleaved from DMSP by the enzyme DMSP lyase, although many non-marine species of bacteria convert methanethiol to DMS.
DMS is also taken up by marine bacteria, but not as rapidly as methanethiol. Although DMS usually consists of less than 25% of the volatile breakdown products of DMSP, the high reactivity of methanethiol makes the steady-state DMS concentrations in seawater approximately 10 times those of methanethiol (~3 nM vs. ~0.3 nM). Curiously, there have never been any published correlations between the concentrations of DMS and methanethiol. This is probably due to the non-linear abiotic and microbial uptake of methanethiol in seawater, and the comparatively low reactivity of DMS. However, a significant portion of DMS in seawater is oxidized to dimethyl sulfoxide (DMSO).
There is a considerable interest in DMS in the scientific literature that focuses on global climate. DMS is thought to play a role in the earth's heat budget by decreasing the amount of solar radiation that reaches the earth's surface.
External links
- DMS and Climate (http://saga.pmel.noaa.gov/review/dms_climate.html)
