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Utilization of oligopeptides by Listeria monocytogenes Scott A

Article Abstract:

Listeria monocytogenes can use oligopeptides containing up to eight residues as a source of amino acids, with its oligopeptide transport system that is presumed to require ATP for translocation. This oligopeptide transport system has a relatively high level of activity. Cell extract from L. monocytogene indicates that oligopeptides are hydrolyzed upon internalization to serve as sources of amino acids for growth. These results may be significant for the understanding of growth of L. monocytogenes in foods that harbor indigenous proteinases and/or proteolytic microorganisms.

Oligopeptides

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Listeria monocytogenes Scott A transports glucose by high-affinity and low-affinity glucose transport systems

Article Abstract:

Listeria monocytogenes uses a high-affinity phosphotransferase system dependent on phosphoenolpyruvate and a low-affinity system mediated by proton motive force to transport glucose. 2-deoxyglucose and 6-deoxyglucose suppress the low-affinity system, while mannose and 2-deoxyglucose suppress the high-affinity system. Glucose and 2-deoxyglucose transport rates are higher in cells and vesicles energized by valinomycin, suggesting that membrane potential may also affect the low-affinity system's uptake.

Analysis, Physiological aspects, Biological transport, Glucose

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Aerobic and anaerobic metabolism of Listeria monocytogenes in defined glucose medium

Article Abstract:

Listeria monocytogenes growing in glucose medium produces lactate, acetate, and acetoin as the end products of aerobic metabolism. Similarly, under anaerobic conditions the end products are acetate, formate, lactate, carbon dioxide and ethanol. L. monocytogenes produces acetoin only during aerobic metabolism. The formation of acetoin indicates metabolic activity of L. monocytogenes during aerobic growth in a glucose defined medium.

Observations, Microbial metabolism

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