As a representative of a genus with species considered to be potential commercial producers of the nutritionally important polyunsaturated fatty acid docosahexaenoic acid (DHA), Thraustochytrium sp. ATCC 26185 was investigated to determine its potential for DHA production and lipid composition. Cells from liquid shake cultures contained 32% (w/w) lipid, 18% of which was nonsaponifiable lipid. The major saturated fatty acids (14:0 and 16:0) comprised up to 59% of the total fatty acids, and DHA was up to 25% after 6 d incubation. Squalene represented 63% of the nonsaponifiable lipid, and cholesterol composed 41% of the total sterols. The phospholipids expected for eucaryotic microbes were detected with phosphatidylcholine as the major phospholipid at 76% of the total. The ultrastructure of this species was similar to other Thraustochytrium species except that the cells did not have surface scales and they contained unusual membrane-like structures that appeared to be associated with oil formation.

The developed CRISPR-Cas9-based genome engineering tool will facilitate functional genomic studies in C. difficile as well as the elucidation of mechanisms related to host-bacteria interaction and pathogenesis of CDI. This will be highly beneficial for the development of innovative strategies for CDI diagnostics and therapies.

Vertical Schottky diodes were fabricated on the bulk GaN substrate with decreasing impurity concentration from N-face to Ga-face. An array of circular Pt Schottky contacts and a full backside Ti/Al/Ni/Au ohmic contact were prepared on the Ga-face and the N-face of the n-GaN substrate, respectively. The Schottky diode exhibits a minimum specific on-state resistance of 1.3 m cm 2 and a maximum breakdown voltage of 600 V, resulting in a figure-ofmerit of 275 MW cm −2 . An ultra-low reverse leakage current density of 3.7 × 10 −4 A cm −2 at reverse bias of 400 V was observed. Temperature-dependent I-V measurements were also carried out to study the forward and reverse transportation mechanisms.

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