The effect of organic matter and oxygen on the degradation of bacterial membrane lipids in marine sediments

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

14

Scientific paper

The biodegradation of purified radiolabelled membrane lipids from a methanogenic bacterium and a pseudomonad were investigated in mangrove, beach and high marsh marine sediments under aerobic and anaerobic conditions. The effect of organic matter on the amount and rate of degradation was also examined by supplementing beach sediments with humic acids. In aerobic sediments, CO 2 was the major product of lipid degradation while under anaerobic conditions both CO 2 and CH 4 were major end products and the overall rates were reduced (up to 40%) relative to aerobic conditions. Total bacterial numbers increased during all incubations with the largest increases occurring in anaerobic sediments supplemented with humic acids. No lipid degradation occurred in aerobic or anaerobic sediments treated with formaldehyde or autoclaving. In low organic beach sediments, the ester-linked phospholipid of the pseudomonad was degraded much more rapidly than the diphytanyl glycerol diether of the methanogen with 69% of the phospholipid degraded in 96 hours versus only 4% of the methanogen lipid. Lipid degradation in both aerobic and anaerobic sediments was highly correlated to organic matter content with increasing amounts of organic matter inhibiting degradation. Long incubations (75 days) of the diphytanyl glycerol ether resulted in 51% degraded to CO 2 in low (0.5%) organic mangrove sediments while only 9% was mineralized in high (10.8%) organic marsh sediments. Physicochemical sorption of membrane lipids to the organic matrix is proposed as a mechanism which protects membrane lipids from microbial attack and degradation.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The effect of organic matter and oxygen on the degradation of bacterial membrane lipids in marine sediments does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The effect of organic matter and oxygen on the degradation of bacterial membrane lipids in marine sediments, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The effect of organic matter and oxygen on the degradation of bacterial membrane lipids in marine sediments will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1773790

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.