Volatiles from nineteen recently genome sequenced actinomycetes.

Area of Science:

• Microbiology
• Metabolomics
• Genomics

Background:

• Actinomycetes are a diverse group of bacteria with sequenced genomes, known to produce various volatile organic compounds (VOCs).
• Understanding the chemical ecology of actinomycetes can provide insights into their ecological roles and potential biotechnological applications.

Purpose of the Study:

• To identify and characterize VOCs produced by nineteen sequenced actinomycete strains.
• To correlate identified volatile compounds with genomic information, particularly terpene cyclase homologs.
• To investigate the biosynthesis of an unusual plant metabolite identified in actinomycetes.

Main Methods:

• Volatile compounds were collected using a closed-loop stripping apparatus (CLSA).
• Analysis was performed using gas chromatography-mass spectrometry (GC/MS).
• Isotopic labeling experiments were used to study metabolite biosynthesis.

Main Results:

• 178 compounds from various classes were identified across the nineteen actinomycete strains.
• The insect pheromone frontalin was detected in Streptomyces varsoviensis.
• The unusual plant metabolite 1-nitro-2-phenylethane was identified and its biosynthesis from phenylalanine investigated.
• Identified terpenes were correlated with terpene cyclase homologs in the genomes.
• A functional homolog of a previously characterized terpene cyclase was identified in Streptomyces rapamycinicus.

Conclusions:

• The study successfully linked microbial VOCs to genomic data and enzyme functions in actinomycetes.
• The findings expand our understanding of actinomycete chemical diversity and metabolic capabilities.
• The identification of frontalin and 1-nitro-2-phenylethane highlights novel aspects of microbial volatile production.