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A novel, Gram-stain-negative, non-motile, rod-shaped yellow bacterium, designated VBW088 T was isolated from a shallow water hydrothermal vent in Espalamaca in the Azores. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain VBW088 T clustered with three type strains of species of the genus Vitellibacter and exhibited a sequence similarity of 97.3 % with Vitellibacter soesokkakensis RSSK-12 T . However, strain VBW088 T and V. soesokkakensis RSSK-12 T exhibited low DNA-DNA relatedness (12.7±3.5 %). Strain VBW088 T was positive for catalase and oxidase. Growth occurred at 10-37 6C, with the optimum at 30 6C, and at pH 6.0-8.0 (optimum pH 6.0) and in up to 5 % (w/v) NaCl with optimum growth at 1-2 % (w/v) NaCl. The major fatty acids (.10 %) were iso-C 15 : 0 (33.5 %) and iso-C 17 : 0 3-OH (32.0 %). The polar lipids detected in strain VBW088 T consisted of phosphatidylethanolamine, one unidentified aminolipid and three unidentified phospholipids. The DNA G+C content of strain VBW088 T was 36.7 mol%. On the basis of phylogenetic inference, DNA-DNA relatedness, chemotaxonomic analysis and physiological data, the isolate represents a novel species of the genus Vitellibacter, for which the name Vitellibacter nionensis sp. nov. is proposed, with the type strain as VBW088 T (5KCTC 32420 T 5MCC 2354 T ).

Increased awareness regarding the harmful effects of ultraviolet (UV)-B radiation has led to the search for new sources of natural UV-B protecting compounds. Mycosporine-like amino acids are one of such promising compounds found in several organisms. Cyanobacteria are ideal organisms for isolation of these compounds due to their compatibility and adaptability to thrive under harsh environmental conditions. In the following investigation, we report the production of shinorine in Leptolyngbya sp. isolated from the intertidal region. Based on the spectral characteristics and liquid chromatography-mass spectrometry analysis, the UV-absorbing compound was identified as shinorine. To the best of our knowledge, this is the first report on the occurrence of shinorine in Leptolyngbya sp. We also investigated the effect of artificial UV-B radiation and periodic desiccation on chlorophyll-a, total carotenoids, and mycosporine-like amino acids (MAAs) production. The UV-B radiation had a negative effect on growth and chlorophyll concentration, whereas it showed an inductive effect on the production of total carotenoids and MAAs. Desiccation along with UV-B radiation led to an increase in the concentration of photoprotective compounds. These results indicate that carotenoids and MAAs thus facilitate cyanobacteria to avoid and protect themselves from the deleterious effects of UV-B and desiccation.

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