Variation in microbial community structure in two boreal peatlands as determined by analysis of phospholipid Fatty Acid profiles

Abstract

Analyses of phospholipid fatty acids (PLFAs) were used to assess variation in community structure and total microbial biomass in two boreal peatlands in Sweden. The total PLFA concentration in peat ranged from 0.16 to 7.0 nmol g of wet peat ؊1 (median, 0.70 nmol g of wet peat ؊1). Principal-component analysis of PLFA data revealed that the degree of depth-related variation in PLFA composition was high among peatland habitats, with general differences between wet sites, with water tables within a few centimeters of the moss surface, and dry sites, with water tables >10 cm below the moss surface. However, variation in PLFA composition over the growing season was negligible. In the principal-component analyses, most PLFAs were determined to be parts of clusters of covarying fatty acids, suggesting that they originated in the same functional groups of microorganisms. Major clusters were formed by monounsaturated (typical of gram-negative eubacteria), terminally branched (gram-positive or anaerobic gram-negative eubacteria), methyl-branched and branched unsaturated (sulfatereducing bacteria and/or actinomycetes), 8 monounsaturated (methane-oxidizing bacteria), and polyunsaturated (eucaryotes) PLFAs. Within the clusters, PLFAs had rather distinct concentration-depth distributions. For example, PLFAs from sulfate-reducing bacteria and/or actinomycetes and those from methane-oxidizing bacteria had maximum concentrations slightly below and at the average water table depth, respectively.

Methane as a Source of Carbon and Energy for Lake Pelagic Food Webs

“…We filtered 100-200 mL of water per depth through duplicate polyvinylidene difluoride 0.2-m filters (Millipore) (Regnell et al 1996). The methods used for lipid extraction, preparation of fattyacid methyl esters (FAMEs), DMDS (dimethyl disulphide) derivatization of monounsaturated fatty acids, and quantification and identification of FAMEs with gas chromatographic methods, have been described previously (Nichols et al 1986, Virtue et al 1996, Sundh et al 1997. While fatty acids from type I methanotrophs were present in most samples, those from type II methanotrophs generally had very low concentrations.…”

The use of fatty acid methyl esters as biomarkers to determine aerobic, facultatively aerobic and anaerobic communities in wastewater treatment systems

“…In environmental sciences, fatty acids evaluation has allowed several authors to estimate the microbial community structure and metabolic activity in polluted soils (Zelles, 1999;Kozdrój & van Elsas, 2001;Pinkart et al, 2002); to identify contamination of surface waters with polluted soil adjacent to agricultural production fields and to wooded riparian zones (Banowetz et al, 2006); to quantify, characterize and compare sessile and planktonic microbial populations in wastewater treatment systems (Werker & Hall, 1998), to evaluate the adaptation of microorganisms to a particular condition, such as acid environments (Quivey et al, 2000), to establish the microbial community distribution in terms of structure (Sundh et al, 1997;Kozdrój & van Elsas, 2001), and to determine the relative changes in abundance of microorganisms, such as bacteria and fungi (Zeller et al, 2001). FAME analysis can be used to assess the physiological status of the microbial community.…”

Microbial oxidation of CH4 at different temperatures in landfill cover soils

“…The PLFA 18:1x8c has been detected almost exclusively in the type II methanotroph genera Methylocystis and Methylosinus [3]. The methanotrophic PLFAs have been used successfully as biomarkers in analyses of samples from CH 4 -rich environments [8,[13][14][15][16][17][18][19][20]].…”