Membrane-associated nuclease activities in mycoplasmas

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Updated: Nov 8, 2026

Kinetic Screening of Nuclease Activity using Nucleic Acid Probes
06:52

Kinetic Screening of Nuclease Activity using Nucleic Acid Probes

Published on: November 1, 2019

F C Minion1, K J Jarvill-Taylor, D E Billings

  • 1Department of Microbiology, Immunology and Preventive Medicine, Iowa State University, Ames 50011.

Journal of Bacteriology
|December 1, 1993
PubMed

Insights

Mycoplasmal membrane nucleases are common but vary between species. These enzymes, important for growth, may help mycoplasmas acquire host DNA.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Biochemistry

Background:

  • Mycoplasmas are bacteria lacking cell walls, often associated with host membranes.
  • Membrane-associated enzymes play crucial roles in microbial physiology and host interactions.

Purpose of the Study:

  • To investigate and characterize membrane-associated nucleases across various mycoplasmal species.
  • To explore the potential role of these nucleases in mycoplasmal growth and host DNA acquisition.

Main Methods:

  • Development of a lambda DNA assay for measuring nuclease activity in whole cells, released fractions, and detergent-disrupted cells.
  • Utilization of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to analyze nuclease protein profiles and determine molecular weights.
  • Screening of 20 mycoplasmal species and 11 Mycoplasma pulmonis strains.

Main Results:

  • Nuclease activities were predominantly membrane-associated and often stimulated by detergent disruption.
  • All tested mycoplasmal species exhibited nuclease activity, with Mycoplasma capricolum showing unique magnesium-dependent and calcium-inhibited characteristics.
  • SDS-PAGE revealed distinct nuclease patterns among species, with no common bands observed across all 20 species.
  • Nuclease patterns of Mycoplasma pulmonis strains suggested potential for strain-level categorization.

Conclusions:

  • Nucleases are significant components of mycoplasmal membranes.
  • These membrane nucleases may facilitate the uptake of host nucleic acids, supporting mycoplasmal growth.
  • Nuclease profiling via SDS-PAGE could be a valuable tool for classifying mycoplasmal strains.

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