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Mycoplasma and bacterial proteins resembling contractile proteins: a review

H Neimark

    The Yale Journal of Biology and Medicine
    |September 1, 1983
    PubMed

    Insights

    Prokaryotes like mycoplasmas may possess actin and myosin-like proteins, potentially explaining their motility and cell shape. Further research is needed to confirm if these proteins are synthesized by the mycoplasma itself.

    Area of Science:

    • Microbiology
    • Cell Biology
    • Biochemistry

    Background:

    • Prokaryotic motility and cell shape maintenance, particularly in wall-less mycoplasmas, remain poorly understood.
    • The presence and function of cytoskeletal and contractile proteins in prokaryotes are under investigation.

    Purpose of the Study:

    • To review existing literature on prokaryotic proteins homologous to eukaryotic cytoskeletal and contractile proteins.
    • To explore the potential role of these proteins in mycoplasma motility and cell shape.

    Main Methods:

    • Literature review of studies describing prokaryotic proteins with sequence homology to actin, myosin, and tropomyosin.
    • Analysis of experimental data on protein binding assays using Mycoplasma pneumoniae preparations.

    Main Results:

    • Prokaryotes exhibit proteins with significant amino acid sequence homology to actin, myosin light chain, and tropomyosin.
    • Mycoplasma pneumoniae protein extracts show binding affinity for heavy meromyosin, anti-actin antibodies, and phalloidin.

    Conclusions:

    • The identified prokaryotic proteins suggest a potential cytoskeletal system analogous to eukaryotic systems.
    • While suggestive, definitive proof is required to confirm that Mycoplasma pneumoniae synthesizes actin-like proteins for its cellular functions.

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