Cytogenetic testing of mutagenic potential of the blue-green bacterium, Plectonema boryanum in experimentally treated mice

Abstract

The mutagenic potential of the prokaryotic blue-green bacterium, Plectonema boryanum in mice treated with its culture against parallel control assayed by chromosome aberration and micronucleus test in bone marrow cells and sperm head abnormalities in epididymes yielded positive results showing time-dependent effect in all the tests and the dose-dependent effect assayed for chromosome aberration only. Further, the treatment of 1 ml dose each of culture (T₁), culture filtrate (T₂), isolated filaments in phosphate buffer (T₃), heat-killed sample (T₄) and cell homogenate-filament DNA (T₅) of P. borayanum to different sets of mice against controls yielded net increase in chromosome aberration frequencies at 48 hr of 9.00% in T₁, 5.00% in T₅ 3.25% in T₃, 1.50% in T₂ and 0.75% in T₄ in decreasing order, suggesting that the genotoxic active principle was largely associated with filament and it was heat labile. The results of positive genotoxic potential of P. boryanum in experimental mice filled up the lacuna of 'Microbes as Living Mutagens' advocated by Manna.