Molecular Method for Determining Sex of Walruses

Abstract: We evaluated the ability of a set of published trans-species molecular sexing primers and a set of walrus-specific primers, which we developed, to accurately identify sex of 235 Pacific walruses (Odobenus rosmarus divergens). The trans-species primers were developed for mammals and targeted the X- and Y-gametologs of the zinc finger protein genes (ZFX, ZFY). We extended this method by using these primers to obtain sequence from Pacific and Atlantic walrus (O. r. rosmarus) ZFX and ZFY genes to develop new walrus-specific primers, which yield polymerase chain reaction products of distinct lengths (327 and 288 base pairs from the X- and Y-chromosome, respectively), allowing them to be used for sex determination. Both methods yielded a determination of sex in all but 1–2% of samples with an accuracy of 99.6–100%. Our walrus-specific primers offer the advantage of small fragment size and facile application to automated electrophoresis and visualization.     

Traits associated with virulence to the aphid Macrosiphoniella sanborni in eighteen isolates of Verticillium lecanii

Eighteen isolates of the entomopathogenic fungus Verticillium lecanii from various world-wide locations, from insect hosts and soil were bioassayed against the aphid Macrosiphoniella sanborni in the laboratory. Virulence ranged from an isolate which achieved 100% mortality and LT 50 value (adults) of 3 days ± 0· 2 at 24 ° C, compared with the least virulent isolates causing less than 10% mortality over 14 days (when treated with an inoculum of 1 × 10⁶ conidiospores/ml). All isolates produced extracellular protease and lipase, irrespective of their virulence. A number of traits were frequently associated with the expression of virulence including fast germination, high sporulation rate, an absence of extracellular amylase activity and high extracellular chitinase activities. Large spore size was not strongly associated with virulence. There were exceptions in each variate studied, suggesting that overall expression of virulence is a result of the total complex of these and other traits still to be determined.     

Determination of aflatoxin levels in peanut butter using HPLC and ELISA procedures: Inter-laboratory comparison

Mycotoxin Research - Six laboratories analyzed portions of the same aqueous acetonitrile extracts of three peanut butters for aflatoxin concentrations by an HPLC procedure (using immunoaffinity...     

Eimeria saudiensis N. Sp. (Apicomplexa: Eimeriidae) from the Arabian Oryx (Oryx leucoryx) in Saudi Arabia

Oocysts of Eimeria saudiensis n. sp. (Apicomplexa: Eimeriidae) are described from the feces of the Arabian oryx, Oryx leucoryx , from the Riyadh Zoo, Saudi Arabia. The oocysts were ellipsoidal or slightly ovoid, 31.2 times 24.5 (24.3–36.5 times 20.0–27.6) μm with a bilayered wall about 1.7 μm thick. The micropyle was covered by a dome-shaped cap. The oocyst residuum was absent, but tiny polar granules were present. The sporocysts were elongate ovoid, 14.3 times 7.2 (11.5–18.5 times 6.0–9.0) μm, had a Stieda body, but lacked a substiedal body. The sporocyst residuum was present, composed of numerous small granules. The sporozoites were elongate club-shaped, and contained two prominent refractile bodies.     

EARLY STARVATION1 specifically affects the phosphorylation action of starch‐related dikinases

Starch phosphorylation by starch‐related dikinases glucan, water dikinase (GWD) and phosphoglucan, water dikinase (PWD) is a key step in starch degradation. Little information is known about the precise structure of the glucan substrate utilized by the dikinases and about the mechanisms by which these structures may be influenced. A 50‐kDa starch‐binding protein named EARLY STARVATION1 (ESV1) was analyzed regarding its impact on starch phosphorylation. In various in vitro assays, the influences of the recombinant protein ESV1 on the actions of GWD and PWD on the surfaces of native starch granules were analyzed. In addition, we included starches from various sources as well as truncated forms of GWD. ESV1 preferentially binds to highly ordered, α‐glucans, such as starch and crystalline maltodextrins. Furthermore, ESV1 specifically influences the action of GWD and PWD at the starch granule surface. Starch phosphorylation by GWD is decreased in the presence of ESV1, whereas the action of PWD increases in the presence of ESV1. The unique alterations observed in starch phosphorylation by the two dikinases are discussed in regard to altered glucan structures at the starch granule surface.