Discovery of environmentally safe anti-fouling agent is currently of considerable interest, due to the continuous impact of biofoulers on the marine habitats and the adverse effects of biocides on the environment. This study reports the anti-adhesion effect of marine living Actinobacteria against fouling strains isolated from submerged panels in marine environments of Iran. The extract of Glycomyces sediminimaris UTMC 2460 affected the biofilm formation of Kocuria sp. and Mesorhizobium sp., as the dominant fouling agents in this ecosystem, up to 93.2% and 71.4%, respectively. The metabolic activity of the fouler bacteria was reduced by the extract up to 17 and 9%, respectively. This indicated the bactericidal potency of the extract on cells in the biofilm state that enables the compound to be effective even once the biofilms are established in addition to the inhibition of biofilm initiation. Moreover, extra polymeric substance (EPS) production by fouling bacteria was reduced by 60–70%. The absence of activities against fouling bacteria in suspension and also the absence of toxic effect on Artemia salina showed the harmless ecological effect of the anti-microfouling extract on the prokaryotic and eukaryotic microflora of the studied Iran marine ecosystem. Metabolic profiling of G. sediminimaris UTMC 2460 revealed the presence of compounds with molecular formulae matching those of known anti-fouling diketopiperazines as major components of the extract. These results suggest that the extract of Glycomyces sediminimaris UTMC 2460 could be used as a potentially eco-friendly viable candidate in comparison to the synthetic common commercial anti-microfouling material to prevent the fouling process in marine habitats of Iran.

A novel Glycomyces strain, designated as MH2460, was isolated from marine sediment collected from 12 m depth in Rostami seaport, Bushehr Province in Iran. On International Streptomyces Project 2 medium it produced branching substrate hyphae that developed into a large number of irregularly shaped spores in 8 days. It showed optimal growth at 25-35 °C, pH 6.0-8.0 and in salinity between 2.5-5 % (w/v) NaCl. Chemotaxonomic and molecular characteristics of the isolate matched descriptions for members of the genus Glycomyces. Whole-cell hydrolysates of strain MH2460 contained meso-diaminopimelic acids along with glucose, ribose and small traces of xylose and galactose. The phospholipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannosides as well as two unidentified phosphoglycolipids, one unidentified phospholipid and an unidentified aminolipid. The predominant menaquinones were MK-11(H4) and MK-10(H4). The fatty-acid pattern was mainly composed of anteiso-C15 : 0, anteiso-C17 : 0, iso-C15 : 0 and iso-C16 : 0. The strain belongs to the genus Glycomyces based on 16S rRNA gene sequence with the highest pairwise sequence identity (98.3 %) with Glycomyces phytohabitans KLBMP 1483. The DNA-DNA hybridization value showed 53.9±2.7 % identity when MH2460 was compared to this reference strain. The G+C content of the DNA was 70.2 mol%. Based on phenotypic, biochemical, chemotaxonomic and genotypic features, strain MH2460 (DSM 103727=UTMC 2460=NCCB 100631) is considered to represent a novel species of the genus Glycomyces, for which the name Glycomyces sediminimaris is proposed.

BACKGROUND Sugar-rich foods are of the main components of daily human meals. These foods with high sugar and low water content kill bacteria. However, osmotolerant yeasts survive and multiply. The aim of this study was to examine the occurrence of intracellular Helicobacter pylori(H. pylori) and Staphylococcus spp. in yeast isolates from sugar-rich foods. METHODS Thirty-two yeast isolates from fresh fruits, dried fruits, commercial foods, and miscellaneous foods were identified by the sequencing of amplified products of 26S rDNA. Fluorescence microscopy and LIVE/DEAD bacterial viability kit were used to examine the occurrence of live bacteria inside the yeast’s vacuole. Immunofluorescence assay was used to confirm the identity of intracellular bacteria as H. pylori and Staphylococcus. Polymerase chain reaction (PCR) was used for the detection of 16S rDNA of H. pylori and Staphylococcus in the total DNA of yeasts. RESULTS Yeasts were identified as members of seven genera; Candida, Saccharomyces, Zygosaccharomyces, Pichia, Meyerozyma, Metschnikowia, and Wickerhamomyces. Intravacuolar bacteria were stained green with a bacterial viability kit, revealing that they were alive. Immunofluorescence assay confirmed the identity of intracellular H. pylori and Staphylococcus spp. PCR results revealed that among the 32 isolated yeasts, 53% were H. pylori-positive, 6% were Staphylococcus-positive, 18.7% were positive for both, and 21.8% were negative for both. CONCLUSION Detection of H. pylori- and Staphylococcus-16S rDNA in yeast isolates from dried fruits, and commercial foods showed the occurrence of more than one kind of endosymbiotic bacterium in yeasts’ vacuoles. While the establishment of H. pylori and Staphylococcus in yeast is a sophisticated survival strategy, yeast serves as a potent bacterial reservoir.

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