Phospholipid and lipopolysaccharide normal and hydroxy fatty acids as potential signatures for methane-oxidizing bacteria

Abstract

The extractable ester‐linked and the lipopolysaccharide (LPS) normal and hydroxy fatty acids of the methylotrophic bacteria Methylosinus trichosporium 0B3B, Methylobacterium organophilum XX, grown on methane and methanol, Mb. organophilum RG and Methylomonas sp. were analysed by capillary gas chromotography‐mass spectrometry (GC‐MS). Precise monounsaturated double bond position and geometry was determined by GC‐MS analysis of the derivatized fatty acids. The three species were readily distinguished based on the extractable fatty acid and LPS hydroxy acid profiles. Type I and Type II methylotrophs can be separated based on the presence of 16‐carbon and 18‐carbon monoenoic fatty acids in the two groups of organisms, respectively. Relatively novel components, 18: 1ω8c, 18: 1ω8t, 18: 1ω7t and 18: 1ω6c were present in Ms. trichosporium, and 16: 1ω8c, 16: 1ω8t, 16: 1ω7t, 16: 1ω5c and 16: 1ω5t were detected in Methylomonas sp. These specific lipids may be used, together with other components, as signatures for these methylotrophic bacteria in manipulated laboratory and environmental samples.

Two Invasive Plants Alter Soil Microbial Community Composition in Serpentine Grasslands

“…The biomarker 16:1x5c is associated with AMF (Olsson et al 1995) and also with Type I methanotrophic bacteria (Nichols et al 1985;Holmes et al 1999) and Gram ()) bacteria (White et al 1996). We confirmed that both goatgrass and starthistle are colonized by AMF in our sites (data not shown).…”

Arbuscular Mycorrhizas, Microbial Communities, Nutrient Availability, and Soil Aggregates in Organic Tomato Production

“…As with Axis 1, factors influencing these PLFA were not revealed in the CCA. The PLFA 18:1 x7t has been associated with gram-negative bacteria (Hurst et al, 1996), Psuedomonas putida (Heipieper et al, 1992) and methane oxidizing bacteria (Nichols et al, 1985). The PLFA 16:1 x5c did not have an important loading score in this analysis.…”

“…The reported AM fungal marker 16:1 x5c was not an important loading score in this analysis, and thus does not appear to have high specificity as an AM fungal marker in this soil. This PLFA is also present in many gram-negative bacteria and type 1 methanotrophs (Nichols et al, 1985;Olsson et al, 1995); therefore, its use as a specific indicator of AM fungi in soil (not roots), needs to be considered carefully.…”

Outer membrane proteins of Methylococcus capsulatus (Bath)

“…Whole cells and debris were removed by centrifuging twice at 5,000 × g for 10 min, and the total membranes were pelleted from the resulting supernatant by centrifugation at 26,000 × g for 1 h. The pellet was resuspended in buffer containing 5 mM MgCl 2 and 2% (v/v) Triton X-100 (Sigma). The suspension was stirred at room temperature for 1 h, and insoluble material was collected by centrifugation at 100,000 × g for 1 h. β-Hydroxy palmitic acid in the membrane preparations was measured by gas chromatography/mass spectrometry essentially as described by Nichols et al (1985). Nonadecanoic acid methyl ester was used as the internal standard.…”