Identification and classification of Croceivirga thetidis sp. nov., a marine Flavobacteriaceae isolated from the hard coral Acropora

Antonie van Leeuwenhoek - A taxonomic investigation using a polyphasic method was conducted to identify a novel marine flavobacterium, designated as DJ-13T, isolated from the hard coral Acropora...     

Isolation of Marine Bacteria by In Situ Culture on Media-Supplemented Polyurethane Foam

Polyurethane foam (PUF) supplemented with various agar media was used in situ to trap marine bacteria and it consequently provided a substrate on which they could be cultivated while exposed to natural seawater in the coral reef area. The bacterial population on the PUF blocks was analyzed by denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction (PCR)-amplified 16S rDNA fragments. Changing the composition of the cultivation medium in the PUF blocks and selecting different sampling sites resulted in different bacteria being detected on the PUF blocks. For example, iron-utilizing (IU) bacteria, siderophore-producing (SP) bacteria, and petroleum-degrading (PD) bacteria were isolated from PUF blocks and it was discovered that IU and SP contained iron and PD contained hydrocarbon. This method opens up the possibility for isolating novel and useful marine bacteria.     

Janibacter corallicola sp. nov., isolated from coral in Palau

A novel Janibacter species is described on the basis of phenotypic, chemotaxonomic and genotypic data. Two bacterial strains were isolated in Palau, which were both Gram-positive, catalase-positive bacteria with meso-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan. The major menaquinone was MK-8(H(4)). Mycolic acids were not detected. The G+C content of the DNA was 70-71 mol%. Comparative 16S rDNA studies of the two isolated strains revealed that they both belonged to the genus Janibacter. DNA-DNA relatedness data revealed that 04PA2-Co5-61(T) and 02PA-Ca-009 belong to the same species, a new species of the genus Janibacter. From these results, Janibacter corallicola sp. nov. is proposed, with the type strain 04PA2-Co5-61(T) (=MBIC 08265(T), DSM 18906(T)).     

Biogenic Polyamines Capture CO2 and Accelerate Extracellular Bacterial CaCO3 Formation

Bacteria, including cyanobacteria, as well as some fungi, are known to deposit calcium carbonate (CaCO₃) extracellularly in calcium-containing artificial medium. Despite extensive investigation, the mechanisms involved in extracellular formation of CaCO₃ by bacteria have remained unclear. The ability of synthetic amines to remove carbon dioxide (CO₂) from natural gas led us to examine the role of biogenic polyamines in CaCO₃ deposition by bacteria. Here, we demonstrated that biogenic polyamines such as putrescine, spermidine, and spermine were able to react with atmospheric CO₂ and the resultant carbamate anion was characterized by using nuclear magnetic resonance (NMR) analysis. Biogenic polyamines accelerated the formation of CaCO₃, and we artificially synthesized the dumbbell-shaped calcites, which had the same form as observed with bacterial CaCO₃ precipitates, under nonbacterial conditions by using polyamines. The reaction rate of calcification increased with temperature with an optimum of around 40 °C. Our observation suggests a novel scheme for CO₂ dissipation that could be a potential tool in reducing atmospheric CO₂ levels and, therefore, global warming.     

Visualisation of Phosphate in Subcalicoblastic Extracellular Calcifying Medium and on a Skeleton of Coral by Using a Novel Probe,Fluorescein-4-Isothiocyanate-Labelled Alendronic Acid

Marine Biotechnology - The overload of nutrients of anthropogenic origin, including phosphate, onto coastal waters has been reported to have detrimental effects on corals. However, to the best of...     

Okicamelliaside, an extraordinarily potent anti-degranulation glucoside isolated from leaves of Camellia japonica

Guided by anti-degranulation assays, we isolated from leaves of Camellia japonica an ellagic acid glucoside named okicamelliaside. The structure was elucidated as 3,4-dioxoloellagic acid 4'-O-β-D-glucopyranoside by spectroscopic and chemical methods. Okicamelliaside was 12,000 times more potent than the antihistaminic drug, ketotifen fumarate, in inhibiting the degranulation of RBL-2H3 cells.     

Isolation and functional analysis of cytochrome P450 CYP153A genes from various environments

The cytochrome P450 CYP153 family is thought to mediate the terminal hydroxylation reactions of n-alkanes. We isolated 16 new P450 CYP153A genes (central region) from various environments such as petroleum-contaminated soil and groundwater, as well as one from the n-alkane-degrading bacterium Alcanivorax borkumensis SK2 (designated P450balk). The sequences of the new P450 genes were extended by PCR to generate full-length chimeric P450 genes, using the N- and C-terminal domains of P450balk. A differential CO-reduced P450 spectral analysis indicated that 8 P450 genes among the 16 chimeric genes were expressed in Escherichia coli to generate a soluble and functional enzyme. The several functional chimeric P450s and P450balk were further fused to the reductase domain of the self-sufficient P450 monooxygenase (P450RhF) at the C-terminus. E. coli cells expressing these self-sufficient P450 chimeric genes converted n-alkanes, cyclohexane, 1-octene, n-butylbenzene, and 4-phenyl-1-butene into 1-alkanols, cyclohexanol, 1,2-epoxyoctane, 1-phenyl-4-butanol, and 2-phenethyl-oxirane, respectively.     

Rare carotenoids, (3R)-saproxanthin and (3R,2'S)-myxol, isolated from novel marine bacteria (Flavobacteriaceae) and their antioxidative activities

We isolated three orange or yellow pigment-producing marine bacteria, strains 04OKA-13-27 (MBIC08261), 04OKA-17-12 (MBIC08260), and YM6-073 (MBIC06409), off the coast of Okinawa Prefecture in Japan. These strains were classified as novel species of the family Flavobacteriaceae based on their 16S rRNA gene sequence. They were cultured, and the major carotenoids produced were purified by chromatographic methods. Their structures were determined by spectral data to be (3R)-saproxanthin (strain 04OKA-13-27), (3R,2'S)-myxol (strain YM6-073), and (3R,3'R)-zeaxanthin (strains YM6-073 and 04OKA-17-12). Saproxanthin and myxol, which are monocyclic carotenoids rarely found in nature, demonstrated significant antioxidative activities against lipid peroxidation in the rat brain homogenate model and a neuro-protective effect from L-glutamate toxicity.