FeedaMail: Microbiology via ola Kala on Inoreader

	Microbiology via ola Kala on Inoreader
	(Sponsor this newsletter) Aeromicrobium halotolerans sp. nov., isolated from desert soil sample Abstract A Gram-positive, aerobic, and non-motile, rod-shaped actinomycete strain, designated YIM Y47T, was isolated from soils collected from Turpan desert, China, and subjected to a polyphasic taxonomic study. Phylogenetic analysis indicated that strain YIM Y47T belonged to the genus Aeromicrobium. YIM Y47T shared highest 16S rRNA gene sequence similarities with Aeromicrobium massiliense JC14T (96.47 %). Growth occurs at 20–45 °C (optimum at 30 °C), pH 6.0–8.0 (optimum at pH 7.0), and salinities of 0–7.0 % NaCl (optimum at 4.0 %). The strain YIM Y47T exhibits chemotaxonomic features with menaquinone-7 (MK-7) as the predominant quinone, C16:0, C18:1ω9c and 10-methyl C18:0 (>10 %) as major fatty acids. The cell-wall peptidoglycan of strain YIM Y47T contained ll-diaminopimelic acid as the diagnostic diamino acid. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, and unknown phospholipids. The G+C content of the genomic DNA of strain YIM Y47T was found to be 44.7 mol%. On the basis of phylogenetic analyses and phenotypic data, it is proposed that strain YIM Y47T should be classified as representing a novel species of the genus Aeromicrobium, with the name Aeromicrobium halotolerans sp. nov. The type strain is YIM Y47T (=KCTC 39113T=CGMCC 1.15063T=DSM 29939T=JCM 30627T). Read More » Isolation and identification of nematode-antagonistic compounds from the fungus Aspergillus candidus Culture medium from an isolate of the fungus Aspergillus candidus was extracted, fractionated and examined to discover compounds antagonistic to plant-parasitic nematodes that are important pathogens of agricultural crops. Column, thin layer and preparative chromatographies and spectral and elemental analyses, were used to isolate and identify two major constituents of an active fraction (Fraction F) obtained from the medium. Compound 1 was identified as 2-hydroxypropane-1, 2, 3-tricarboxylic acid (citric acid). Compound 2 was identified as 3-hydroxy-5-methoxy-3-(methoxycarbonyl)-5-oxopentanoic acid, an isomer of 1, 2-dimethyl citrate. Compound 1 and a citric acid standard, each tested at 50 mg mL–1 in water, decreased hatch from eggs of the plant-parasitic nematode Meloidogyne incognita by more than 94%, and completely immobilized second-stage juveniles after 4–6 days exposure. Fraction F and Compounds 1 and 2 decreased the mobility of adults of the plant-parasitic nematode Ditylenchus destructor in vitro. Fraction F (25 mg mL–1) inhibited mobility >99% at 72 hrs. Compounds 1 and 2 (50 mg mL–1) each inhibited mobility more than 25% at 24 hr and more than 50% at 72 hr. This is the first assignment of nematode-antagonistic properties to specifically identified A. candidus metabolites. Read More » Permissiveness of freshly isolated environmental strains of amoebae for growth of Legionella pneumophila Legionella pneumophila is a pathogenic bacterium commonly found in water and responsible for severe pneumonia. Free-living amoebae are protozoa also found in water, which feed on bacteria by phagocytosis. Under favorable conditions, some L. pneumophila are able to resist phagocytic digestion and even multiply within amoebae. However, it is not clear whether L. pneumophila could infect at a same rate a large range of amoebae or if there is some selectivity towards specific amoebal genera or strains. Also, most studies have been performed using collection strains and not with freshly isolated strains. In our study, we assess the permissiveness of freshly isolated environmental strains of amoebae, belonging to three common genera (i.e. Acanthamoeba, Naegleria and Vermamoeba), for growth of L. pneumophila at three different temperatures. Our results indicated that all the tested strains of amoebae were permissive to L. pneumophila Lens and that there was no significant difference between the strains. Intracellular proliferation was more efficient at a temperature of 40°C. In conclusion, our work suggests that, under favorable conditions, virulent strains of L. pneumophila could equally infect a large number of isolates of common freshwater amoeba genera. Read More »
	(Sponsor this newsletter)
	Delievered to you by Feedamail. Unsubscribe

from #Med Blogs by Alexandros G.Sfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/1oCBvtK
via IFTTT