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Characterizing Mediated Extracellular Electron Transfer in Lactic Acid Bacteria with a Three-Electrode, Two-Chamber Bioelectrochemical System
Published on: August 23, 2024
Plasminogen activation by lactic acid bacteria.
1NARO Institute of Livestock and Grassland Science, Tsukuba, Ibaraki 305-0901, Japan. nomura@affrc.go.jp
Bioscience, Biotechnology, and Biochemistry
|August 11, 2012
Summary
Certain lactic acid bacteria activate plasminogen. Lactococcus lactis subsp. lactis biovar diacetylactis NIAI C59 exhibits significant plasminogen activator ability, showing thermal stability and optimal activity at high pH.
Area of Science:
- Microbiology
- Biochemistry
- Enzymology
Background:
- Plasminogen activation is crucial for fibrinolysis.
- Lactic acid bacteria (LAB) are known for diverse enzymatic activities.
- Investigating LAB for novel plasminogen activators is of interest.
Purpose of the Study:
- To screen lactic acid bacteria for plasminogen activation.
- To characterize the plasminogen activator from a promising strain.
Main Methods:
- Incubation of plasminogen with various LAB strains.
- Measurement of plasmin activity.
- Characterization of the activator's stability (pH, temperature) and production kinetics.
Main Results:
- Three out of 15 LAB strains showed significant plasminogen activation.
- Lactococcus lactis subsp. lactis biovar diacetylactis NIAI C59 displayed the highest activity, activating both human and bovine plasminogen.
- The activator was thermally stable across a wide pH range (3.0-9.0) and its activity increased with cultivation time, peaking after 21 hours.
Conclusions:
- Lactococcus lactis subsp. lactis biovar diacetylactis NIAI C59 is a potent source of plasminogen activator.
- The enzyme exhibits robust stability, suggesting potential applications in biotechnology and medicine.
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