Constancy of Characteristics in the Streptomycetes

Abstract

A total of 150 Streptomyces strains isolated from soil was studied during a 3-year period in regard to constancy and variation of the following characteristics: sporophore micromorphology, color of the aerial and substrate mycelium, surface configuration of the spores, assimilation of carbon compounds, production of H2S and melanoid pigment, and reduction of nitrates. A remarkable constancy in the following characteristics was found: (i) sporophore micromorphology When only three of the seven morphological series of Pridham et al. were developed on tomato paste-oatmeal agar or yeast extract-malt extract agar; (ii) color of the aerial mycelium if only four fundamental colors are distinguished (white to cream or buff shades; yellow to orange or brown; pink to cinnamon, red or pinkish tan to lavender; and green to gray or blue); (iii) surface configuration of the spores divided in two types (smooth and warty to spinous or hairy); (iv) assimilation of five carbon compounds (arabinose, xylose, rhamnose, raffinose, and mannitol); (v) production of H2S on Difco peptone-iron agar supplemented with 0.1 % Difco yeast extract; and (vi) production of melanoid pigment on peptone agar, giving similar results to those of the H2S test. Color of the substrate mycelium, size and shape of the spores, and reduction of nitrates should be used only as complementary data in the species descriptions, owing to their inconsistency and unreliability. Various cooperative studies of taxonomic problems in the genus Streptomyces have been undertaken. Among them are those of the First International Cooperative Work on criteria

STREPTOMYCES SPECIES COMPRISING THE BLUE-SPORE SERIES

“…Color becomes taxonomically significant when it can be correlated with other features or characteristics. Sanchez-Marroquin (1962) proposed the reduction of spore-color ranges to four. He would combine the green-, gray-, and bluespored forms.…”

Production of Hydrogen Sulfide by Streptomycetes and Methods for its Detection

“…However, this test was not generally applied to streptomycetes until the work of Tresner and Danga (1958), who studied a large number of strains with Peptone Iron Agar. Since this study, several workers have used hydrogen sulfide production as a test for streptomycetes (Turri and Silvestri, 1960;Prauser and Meyer, 1961;Pridham and Lyons, 1961;Sanchez-Marroquin, 1962). The results of Turri and Silvestri (1960) and Prauser anid Meyer (1961) cast con1siderable doubt on the value of using Peptone Iron Agar as a means of detecting hydrogen sulfide production by streptomycetes.…”