Coronamycins, peptide antibiotics produced by a verticillate Streptomyces sp. (MSU-2110) endophytic on Monstera sp.

Abstract

Coronamycin is a complex of novel peptide antibiotics with activity against pythiaceous fungi and the human fungal pathogen Cryptococcus neoformans. It is also active against the malarial parasite, Plasmodium falciparum, with an IC 50 of 9?0 ng ml "1. Coronamycin is produced by a verticillate Streptomyces sp. isolated as an endophyte from an epiphytic vine, Monstera sp., found in the Manu region of the upper Amazon of Peru. Bioassay-guided fractionation of the fermentation broths of this endophyte on silica gel and HPLC chromatography yielded two principal, inseparable, peptides with masses of 1217?9 and 1203?8 Da. Three other minor, but related components, are also present in the preparation. Amino acid analysis of coronamycin revealed residues of component 1, component 2, methionine, tyrosine and leucine at a ratio of 2 : 2 : 1 : 1 : 3. Other compounds with antifungal activities are also produced by this endophytic streptomycete.

Isolation and antimicrobial activities of actinobacteria closely associated with liquorice plants Glycyrrhiza glabra L. and Glycyrrhiza inflate BAT. in Xinjiang, China

“…Endophytes are microorganisms that live inside plant tissues by symbiotic, parasitic or mutualistic means without causing immediately overt negative effects (Stone et al, 2000). Endophytes may participate in the metabolic pathways of plant hosts and produce analogous or novel bioactive compounds (Ezra et al, 2004;Stierle et al, 1993;Taechowisan et al, 2005).…”

A question concerning the identity of Streptomyces sp. MSU-2110

“…MSU-2110 that appeared in the April issue of Microbiology (Ezra et al, 2004). These workers suggest that we had mistakenly identified our coronamycin-producer as a streptomycete based on morphological observations and 16S rRNA gene sequence data.…”

“…The isolate, MSU-2110, has multiple organized chains of spores arising from verticillated hyphae, as shown in the original Microbiology article (Ezra et al, 2004). It does turn out that lemon-shaped spores, in chains, are known from streptomycetes including Streptomyces sp.…”

“…Streptomyces hygroscopicus (Miyadoh, 1997). Also, the spore size of strain MSU-2110 in the environmental scanning electron micrographs are more in the range of 2 mm while in the regular scanning electron micrographs the spores may appear larger due to the gold coating that was used on the specimens (Ezra et al, 2004).…”

Functionalized para-substituted benzenes as 1,8-cineole production modulators in an endophytic Nodulisporium species

“…Frequently these secondary metabolites are antimicrobial substances, but compounds able to deter herbivory and increase rates of nutrient uptake have also been reported (Clay, 1996;Malinowski et al, 2000). The variety of secondary metabolites produced by endophytic fungi reflects the diversity of the organisms themselves, and includes compounds such as taxol, novel antibiotics, quorum-sensing inhibitors and fuel-associated hydrocarbons (Castillo et al, 2003;Ezra et al, 2004c;Mends et al, 2012;Li et al, 2001;Stierle et al, 1993;Strobel et al, 2008).…”