Cell wall acyl type in some strains of Streptoverticillium and Streptomyces.

Abstract

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

Triggering the expression of a silent gene cluster from genetically intractable bacteria results in scleric acid discovery

“…Deletion of the four-gene operon sclQ1-4 did not completely abolish scleric acid production, which could be explained by the fact that Streptomyces species are known to produce glycolic acid by other means. 30 As expected enrichment of the culturing medium with the key biosynthetic precursors i.e. L-proline, benzoic acid and glycolic acid led S. albus/scl ∆sclM4 to produce scleric acid in higher titres than when cultured in the supplemented minimal medium ( Supplementary Fig.…”

“…Residual scleric acid production was detected from S. albus/scl ∆sclM4 ∆sclQ1-4; this could be explained by the fact that glycolic acid is known to be produced by Streptomyces species in particular for the biosynthesis of Nglycolylmuramic acid. 30 Addition of 5 mM glycolic acid to the culture medium of S. albus/scl ∆sclM4 ∆sclQ1-4 also resulted in scleric acid being produced in similar level to that observed with S. albus/scl ∆sclM4 ( Supplementary Fig. S14).…”

Triggering the expression of a silent gene cluster from genetically intractable bacteria results in scleric acid discovery

“…3a), confirming the essential role of SclN and SclA. Residual scleric acid production was detected from S. albus / scl Δ sclM4 Δ sclQ1-4 ; this could be explained by the fact that glycolic acid is known to be produced by Streptomyces species in particular for the biosynthesis of N -glycolylmuramic acid 36. Addition of 5 mM glycolic acid to the culture medium of S. albus / scl Δ sclM4 Δ sclQ1-4 also resulted in scleric acid being produced in similar level to that observed with S. albus / scl Δ sclM4 (ESI Fig.…”