A comparative study of the lipid composition of 26 strains (including type strains) of marine Gammaproteobacteria belonging to the genera Shewanella, Alteromonas, Pseudoalteromonas, Marinobacterium, ...Microbulbifer, and Marinobacter was carried out. The bacteria exhibited genus-specific profiles of ubiquinones, phospholipids, and fatty acids, which can serve as reliable chemotaxonomic markers for tentative identification of new isolates. The studied species of the genus Shewanella were distinguished by the presence of two types of isoprenoid quinones, namely, ubiquinones Q-7 and Q-8 and menaquinones MK-7 and MMK-7; five phospholipids typical of this genus, namely, phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), lyso-PE, and acyl-PG; and the fatty acids 15:0,16:0,16:1 (n-7), 17:1 (n-8), i-13:0, and i-15:0. The high level of branched fatty acids (38-45%) and the presence of eicosapentaenoic acid (4%) may serve as criteria for the identification of this genus. Unlike Shewanella spp., bacteria of the other genera contained a single type of isoprenoid quinone: Q-8 (Alteromonas, Pseudoalteromonas, Marinobacterium, and Microbulbifer) or Q-9 (Marinobacter). The phospholipid compositions of these bacteria were restricted to three components: two major phospholipids (PE and PG) and a minor phospholipid, bisphosphatidic acid (Alteromonas and Pseudoalteromonas) or DPG (Marinobacterium, Microbulbifer, and Marinobacter). The bacteria exhibited genus-specific profiles of fatty acids.
Twenty-five strains of epiphytic marine bacteria isolated from the brown algaeFucus evanescens andChorda filum and fifty-three bacteria isolated from the sea cucumberApostichopus japonicus were ...screened for fucoidanases using fucoidans prepared from the brown algaeF. evanescens, Laminaria cichorioides, andL japonica. Eighteen bacterial epiphytes and thirty-eight bacterial isolates from the sea cucumber were found to contain fucoidanases, which were able to hydrolyze either all of the fucoidans studied or some of them. Bacteria of the generaCytophaga andAlteromonas/Pseudoalteromonas exhibited the highest fucoidanase activities, which, however, did not exceed the activity of fucoidanases from the already known sources.
It was found that Pseudoalteromonas citrea strains KMM 3296 and KMM 3298 isolated from the brown algae Fucus evanescens and Chorda filum, respectively, and strain 3297 isolated from the sea cucumber ...Apostichopus japonicus are able to degrade fucoidans. The fucoidanases of these strains efficiently degraded the fucoidan of brown algae at pH 6.5-7.0 and remained active at 40-50 degrees C. The endo-type hydrolysis of fucoidan resulted in the formation of sulfated alpha-L-fucooligosaccharides. The other nine strains of P. citrea studied (including the type strain of this species), which were isolated from other habitats, were not able to degrade fucoidan.
Pathogenic properties of thermostable toxin responsible for pathogenicity of Yersinia pseudotuberculosis were experimentally studied. The toxin exerted a pronounced polyorgan cytopathogenic effect ...with predominating degenerative destructive changes and membranolytic effect on cell ultrastructure of parenchymatous organs. The toxin is believed to be directly involved in the development of typical pathomorphological picture of pseudotuberculosis, which confirms its pathogenetic role.
N-Acetyl-(1) and N,N-diacetyl-(2) tryptamines were isolated from the butanol extract of culture medium of the new marine bacterium Roseivirga echinicomitans KMM 6058 super(T). The structures of the ...compounds were proved using mass spectrometry, UV, PMR, and super(13)C NMR spectroscopy and by comparing these data with mass and NMR spectra of synthetic samples of 1 and 2. Compound 2 was isolated from a natural source and synthesized for the first time. The cytotoxic activity of the compounds was studied using Erlich carcinoma tumor cells, murine erythrocytes, and sperm and egg cells of the sea urchin Strongylocentrotus intermedius.
