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Piliation and colonial morphology among laboratory strains of meningococci

I W DeVoe, J E Gilchrist

    Journal of Clinical Microbiology
    |April 1, 1978
    PubMed

    Insights

    Colonial morphology and piliation in Neisseria meningitidis show complex variations. Correlations between these traits are infrequent, suggesting independent regulation in this bacterium.

    Area of Science:

    • Microbiology
    • Bacterial genetics
    • Pathogen research

    Background:

    • Neisseria meningitidis is a significant human pathogen.
    • Understanding its phenotypic variations is crucial for epidemiology and control.
    • Colonial morphology and piliation are key bacterial surface characteristics.

    Purpose of the Study:

    • To investigate the relationship between colonial morphology and piliation in Neisseria meningitidis.
    • To identify different colony types and their associated pilus expression.
    • To determine the frequency of correlations between these two traits.

    Main Methods:

    • Culturing twelve Neisseria meningitidis strains from diverse serogroups.
    • Characterizing colony morphology, identifying six distinct types (M1-M6).
    • Analyzing piliation status and pilus characteristics in different colonial variants.

    Main Results:

    • Most strains exhibited a predominant M1 colonial type, resembling Neisseria gonorrhoeae T4.
    • Observed variations included piliated/non-piliated cells, colonial changes without piliation changes, and variants with different pili.
    • Established that correlations between piliation and colony morphology are not the norm.

    Conclusions:

    • Colonial morphology and piliation in Neisseria meningitidis exhibit diverse and often independent variations.
    • The study highlights exceptions rather than rules in the correlation between these phenotypes.
    • Further research may elucidate the genetic mechanisms underlying these independent variations.

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