The cell wall acyl type was determined for representative strains from major taxonomic clusters within the genera Streptomyces and Streptoverticillium. Streptomycete strains contained between 2.5 and 7.5 nmol of glycolic acid/mg of cells, confirming previous reports of the presence of an acetyl muramic acid. Streptoverticillium strains contained between 5.0 and 8.0 nmol glycolic acid/mg of cells, indicating that they also have an acetyl rather than glycolyl muramic acid. The findings are discussed in the context of differences in lysozyme sensitivity between members of the two genera and in connection with the mechanism of lysozyme resistance in Streptoverticillum.Strains belonging to the genera Streptoverticillium and Streptomyces exhibit a number of common characteristics. They have a wall chemotype I (1, 2) and DNA rich G±C (3), share high DNA homology values (4-6) and are attacked by the same phages (7, 8). They also contain similar menaquinones (9-11), fatty acids and polar lipids (12, 13). Phenetic classifications (14,15) have also shown a close relationship between the two genera but the very distinctive morphology of the sporulating mycelium in Streptoverticillium (16,17) continues to be used for distinguishing the genera (18,19).We have recently shown (20) that all Streptoverticillium strains tested were able to grow in the presence of lysozyme (468 units/ml). The concentration chosen was within the range used by other workers and allowed comparison with previous work (21). The majority of Streptomyces strains tested were inhibited at the concentration of lysozyme used. Streptomyces strains that were able to grow in the presence of lysozyme belong to cluster 61 of cluster group F (15) which includes Streptomyces lavendulae and Streptoverticillium species, or to cluster-group B (15) named Streptomyces rimosus. Species in the first cluster had already been shown to have a high phenetic relationship with the streptoverticillia (14,15) and the Streptomyces rimosus cluster group was recovered at some 493
Members of the genera Streptomyces, Micromonospora, Nocardia and Streptosporangium were effectively inhibited by oxytetracycline at concentrations tolerated by a majority of the Streptoverticillium strains tested. The incorporation of this antibiotic into a primary isolation medium significantly increased the numbers of Streptoverticillium spp. isolated from soils.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.