Antimicrobial Chlorinated 3-Phenylpropanoic Acid Derivatives from the Red Sea Marine Actinomycete Streptomyces coelicolor LY001.

Lamiaa A Shaala,Sameh S Elhady,Torki A Alzughaibi,Diaa T A Youssef

doi:10.3390/md18090450

Abstract

The actinomycete strain Streptomyces coelicolor LY001 was purified from the sponge Callyspongia siphonella. Fractionation of the antimicrobial extract of the culture of the actinomycete afforded three new natural chlorinated derivatives of 3-phenylpropanoic acid, 3-(3,5-dichloro-4-hydroxyphenyl)propanoic acid (1), 3-(3,5-dichloro-4-hydroxyphenyl)propanoic acid methyl ester (2), and 3-(3-chloro-4-hydroxyphenyl)propanoic acid (3), together with 3-phenylpropanoic acid (4), E-cinnamic acid (5), and the diketopiperazine alkaloids cyclo(l-Phe-trans-4-OH-l-Pro) (6) and cyclo(l-Phe-cis-4-OH-d-Pro) (7) were isolated. Interpretation of nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HRESIMS) data of 1–7 supported their assignments. Compounds 1–3 are first candidates of the natural chlorinated phenylpropanoic acid derivatives. The production of the chlorinated derivatives of 3-phenylpropionic acid (1–3) by S. coelicolor provides insight into the biosynthetic capabilities of the marine-derived actinomycetes. Compounds 1–3 demonstrated significant and selective activities towards Escherichia. coli and Staphylococcus aureus, while Candida albicans displayed more sensitivity towards compounds 6 and 7, suggesting a selectivity effect of these compounds against C. albicans.

Highlights

The marine actinomycetes represent a vital source of biologically active secondary metabolites and a promising future source for drug discovery
The resulting sequence of the actinomycete strain was searched for homology with Basic Local Alignment Search Tool (BLAST) in the GenBank
The alignment with reported sequences in the GenBank showed that the LY001 isolate belongs to the genus Streptomyces and similarity with the strain Streptomyces coelicolor AB588124

Summary

Introduction

The marine actinomycetes represent a vital source of biologically active secondary metabolites and a promising future source for drug discovery. It is well known that marine tunicates and sponges are highly associated with symbiotic microbes [1,2,3]. There are very few reports about investigation of. Red Sea actinomycetes for their chemical diversity and biomedical importance [4]. Streptomycetes represent a group within the actinomycetes with an economical importance and represent a vigorous source of different bioactive secondary metabolites [5]. Mar. Drugs 2020, 18, 450; doi:10.3390/md18090450 www.mdpi.com/journal/marinedrugs

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Conclusion