Pioneered by Microbial Insights founder Dr. D.C. White, phospholipid fatty acid analysis (PLFA) is used to quantify total viable biomass in water or soil samples and provide a general profile of the microbial community. Phospholipid fatty acids are a main component of the cell membrane (“the skin”) of all microbes.
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PLFA ADVANTAGES:
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ACCURATE
PLFA are extracted directly from a sample removing the need to grow the bacteria and eliminating biases associated with traditional approaches (e.g., plate counts and MPNs).
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LIVING
PLFA decomposes quickly upon cell death, so quantification of total PLFA in a sample represents the concentration of viable (living) cells. Results reported as cells/mL, cells/g, etc.
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PROFILE
Some types of microorganisms produce specific types or “signature” PLFA biomarkers. While not specific like DNA based techniques, the relative proportions of these groups of PLFA biomarkers provide a general profile of the microbial community highlighting groups such as anaerobic metal reducers, sulfate reducers, fermenters, and fungi.
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STATUS
Proteobacteria modify specific PLFA biomarkers during periods of slow growth or in response to environmental stress providing an indicator of their physiological status and health.
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ADAPTABLE
PLFA analysis is conducted as part of Stable Isotope Probing (SIP), an innovative technique in which Bio-Traps® amended with a 13C labeled contaminant are used to conclusively determine whether biodegradation is occurring.
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FLEXIBLE
Analysis can be performed on almost any type of sample (water, soil, sediments, Bio-Traps® and others).
HOW TO USE PHOSPHOLIPID FATTY ACID ANALYSIS:
Use PLFA to quantify total living microbial biomass and produce a general profile of the community composition.
Use PLFA to help answer…
- What is the total viable biomass concentration?
- Do subsurface conditions support microbial growth?
- Has microbial biomass increased in response to amendments or other site activities?
- What is the microbial community composition?
- Has the microbial community composition changed? Does it reflect redox conditions?
- Are the microbial communities in soils, particularly agricultural soils, diverse and healthy?
- As part of a stable isotope probing (SIP) study, phospholipid fatty acid analysis helps answer the question “Is biodegradation is occurring?”