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Agrobacterium tumefaciens-mediated transformation (ATMT) is examined for Mortierella alpina 1S-4 transformation by using the uracil-auxotrophic mutant of Mortierella alpina 1S-4 as a host strain and the homologous ura5 gene as a selectable marker gene. The ATMT system is effective and suitable for the industrial strain Mortierella alpina 1S-4 and is a useful tool for basic mutagenesis research and for industrial breeding of this strain.

Thirty-four strains of docosahexaenoic acid (DHA)-producing microorganisms were newly isolated from brackish areas in Japan. These strains showing various compositions of fatty acids. Especially, the fatty acids produced by one of the strains, named D31, had a high DHA content (over 60 % of the total fatty acids) and the simple fatty acid composition (16:0, 18:0, 18:1 and DHA without any other polyunsaturated acids). Although most oleaginous microorganisms accumulate DHA as triacylglycerol, the strain D31 accumulated DHA mainly as a polar lipid (79.4 % of total DHA), especially as phosphatidylcholine (71.4 % of polar DHA). This strain D31 was identified as a related species of Crypthecodinium cohnii on the basis of phylogenetic analysis. Crypthecodinium sp. D31 showed high DHA productivity when cultivated in a medium containing glycerol as the carbon source and a mixture of yeast extract and polypeptone as the nitrogen sources, with a salinity that was equivalent to 50 % of that of seawater and a pH in the acidic range (

Details a structural analysis of conjugated linoleic acid (CLA) produced by Lactobacillus plantarum, as well as factors affecting isomer production using proton nuclear magnetic resonance spectroscopy. Data showing that the bacterium produced two CLA isomers from linoleic acid; Addition of L-serine, glucose, silver nitrate or sodium chloride to the reaction mixture reducing production in the latter.

The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum., (© 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)