Characterization of <Emphasis Type="Italic">twist</Emphasis> and <Emphasis Type="Italic">snail</Emphasis> gene expression during mesoderm and nervous system development in the polychaete annelid <Emphasis Type="Italic">Capitella</Emphasis> sp. I

To investigate the evolutionary history of mesoderm in the bilaterian lineage, we are studying mesoderm development in the polychaete annelid, Capitella sp. I, a representative lophotrochozoan. In this study, we focus on the Twist and Snail families as candidate mesodermal patterning genes and report the isolation and in situ expression patterns of two twist homologs (CapI-twt1 and CapI-twt2) and two snail homologs (CapI-sna1 and CapI-sna2) in Capitella sp. I. CapI-twt1 is expressed in a subset of mesoderm derivatives during larval development, while CapI-twt2 shows more general mesoderm expression at the same stages. Neither twist gene is detected before the completion of gastrulation. The two snail genes have very distinct expression patterns. At cleavage and early gastrula stages, CapI-sna1 is broadly expressed in precursors of all three germ layers and becomes restricted to cells around the closing blastopore during late gastrulation; CapI-sna2 expression is not detected at these stages. After gastrulation, both snail genes are expressed in the developing central nervous system (CNS) at stages when neural precursor cells are internalized, and CapI-sna1 is also expressed laterally within the segmental mesoderm. Based on the expression patterns in this study, we suggest a putative function for Capitella sp. I twist genes in mesoderm differentiation and for snail genes in regulating CNS development and general cell migration during gastrulation. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

An Inhibitor of S-Hemolysin,SHI, Produced by Streptomyces sp. Strain No. 6288

Streptomyces sp. strain No. 6288 produces S-Hemolysin, which is a unique phospholipase C with a high substrate specificity for sphingomyelin. Moreover, the strain also produced two kinds of phospholipase inhibitors, designated as SHI and S-PLI, in different phases of cultivation. The purified SHI was shown to be a basic substance containing an amino group and glycoside moiety, and it was a more effective inhibitor of S-Hemolysin and sphingomyelinase from Streptomyces sp. with a higher substrate specificity for sphingomyelin than α-toxin from Clostridium perfringens.     

A new species of Trichogramma (Hymenoptera: Trichogrammatidae) parasitic on eggs of the alderfly Sialis melania (Neuroptera: Sialidae) from Japan,with comments on its phylogeny and male wing polymorphism

A new species of Trichogramma that parasitizes Sialis melania eggs is described as Trichogramma tajimaense Yashiro, Hirose and Honda, sp. nov. from Japan. Its phylogenetic position is based on a DNA‐based analysis, and data regarding its male wing polymorphism are also presented. The view that T. tajimaense is closely related to T. semblidis, another parasitoid of Sialis eggs, is supported by the results of a phylogenetic analysis, as well as by the biological and morphological similarities between both species. Trichogramma tajimaense is also similar in male wing polymorphism to T. kurosuae, a gregarious egg parasitoid of the lepidopteran Ivela auripes, as both Trichogramma species exhibit male wing trimorphism (fully alate, brachypterous and apterous forms) in contrast to the male wing dimorphism (fully alate and apterous forms) of T. semblidis. However, no phylogenetic analysis reveals a close relationship between T. tajimaense and T. kurosuae, and a difference exists between these two species in the mean percentage of flightless (brachypterous and apterous) males that emerge from a host egg mass; 96% of T. tajimaense males are incapable of flight, whereas about 50% of T. kurosuae males are flightless. Because all or almost all males of T. semblidis parasitizing Sialis eggs are apterous, T. tajimaense is more similar to T. semblidis than to T. kurosuae in the proportion of flightless males. In addition, male wing polymorphisms of Trichogramma in relation to mating systems could also show a similarity between T. tajimaense and T. semblidis when considering both species as quasi‐gregarious parasitoids of Sialis eggs.     

一中国白酒酒曲中的丝状真菌菌群

采用6种不同的培养基,分别于25℃、32℃、42℃以及50℃培养分离从而对某一中国白酒酒曲中的丝状真菌菌群进行研究.从酒曲中共分离得到886株丝状真菌,分属于接合菌,子囊菌和无性型真菌的20属,45种.其中最为丰富的是无性型真菌(28种),其次是接合菌(10种)和子囊菌(7种).对发酵起主要作用的为那些嗜热和耐热的种属,包括:宛氏拟青霉,伞枝梨头霉,梳棉状嗜热丝孢菌,微小根毛霉,金孢霉属一种和红曲属的几个种.文中还对一些在发酵中起重要作用的丝状真菌的特性进行了探讨.     

Resistance to Spodoptera exigua in Apium prostratum

Two Apium accessions were compared with the commercial cultivar Tall Utah 52–70R (A. graveolens [L.]) for resistance to Spodoptera exigua (Hübner)(Lepidoptera: Noctuidae). Oviposition rate was not significantly different between the three genotypes. In all accessions, eggs were usually placed on the upper half of the plants. Implications of this oviposition pattern on S. exigua management in celery are discussed. The wild species A. prostratum ssp prostratum var filiform (A230) showed a significantly higher resistance to S. exigua than 52–70R. The levels of carcinogenic and mutagenic linear furanocoumarins in the commercial cultivar 52–70R (1.41 g/g in the petioles; 5.85 g/g in the leaves) and in the plant accession A. nodiflorum (5.40 g/g in the petioles; 2.99 g/g in the leaves) were far below the concentration reported to produce acute contact dermatitis (18.0 g/g). The levels of furanocoumarins in A. prostratum petioles (186.14 g/g) and leaves (326.45 g/g) were 10 and 18 times higher, respectively, than the concentration known to cause contact dermatitis. However, resistance in A. prostratum was primarily due to non-preference and the linear furanocoumarins did not induce non-preference. Therefore, the resistance shown by this plant accession does not appear to be furanocoumarin-based and may be suitable for transfer to commercial celery for use in S. exigua management.     

诺卡氏菌对油酸的羟基化作用

诺卡氏菌(Nocardia sp．N13)休止细胞对油酸(顾-9-十八碳烯酸)进行羟基化作用。用休止细胞转化时最适温度为30℃,最适pH为6．5,当菌体(干菌)与底物的最适比例为20 ：1对,对油酸的转化率为83．4％,不同的表面活性剂影响转化的效果。N13休止细胞在磷酸缓冲液中重复转化3次仍可保持50％左右的转化率。红外光谱、质谱、棱磁共振鉴定产物为10－羟基硬脂酸。     

Heteroduplex mobility assay for the identification of Listeria sp and Listeria monocytogenes strains: application to characterisation of strains from sludge and food samples

One hundred and ten Listeria sp. isolates from sewage sludge were identified according to phenotypic and genotypic methods. The Listeria sp. strains isolated from five types of sludge from three sewage treatment plants in Angers (France) and the surrounding area included L. monocytogenes (55.5%), L. innocua (29.1%), L. seeligeri (13.6%) and L. welshimeri (1.8%). The majority of L. monocytogenes strains belonged to serotypes 4b, 1/2b and 1/2a. Moreover, a heteroduplex mobility assay based on the 16S rRNA sequences was tested for its ability to identify the six species of the genus Listeria. This study, performed on 283 Listeria sp. strains from human, food and sewage sludge samples, showed that all the species were distinguishable from one another. L. innocua and L. seeligeri showed respectively three and two distinct banding patterns. Within L. monocytogenes, four groups (I-IV) were defined. The majority of food and environmental isolates were clustered in group I and it is noteworthy that group IV clustered epidemiologic isolates and strains belonging to serotypes 4b, 1/2a and 1/2b.     

Genomic Analysis of the Mycoparasite Pestalotiopsis sp. PG52

Pestalotiopsis sp. is a mycoparasite of the plant pathogen Aecidium wenshanense. To further understand the mycoparasitism mechanism of Pestalotiopsis sp., we assembled and analyzed its genome. The genome of Pestalotiopsis sp. strain PG52 was assembled into 335 scaffolds and had a size of 58.01 Mb. A total of 20,023 predicted genes and proteins were annotated. This study compared PG52 with the mycoparasites Trichoderma harzianum, Trichoderma atroviride, and Trichoderma virens. This study reveals the entirely different mycoparasitism mechanism of Pestalotiopsis compared to Trichoderma and reveals this mycoparasite’s strong ability to produce secondary metabolites.     

Coccidia from the Tiger Salamander, Ambystoma tigrinum, in Northeastern Colorado and in Northern New Mexico

SYNOPSIS. Oocysts of Eimeria ambystomae Saxe, 1955, Eimeria microcapi sp. n., and Eimeria urodela sp. n. are described from the tiger salamander, Ambystoma tigrinum , collected in Colorado and New Mexico. The oocysts of E. ambystomae are ellipsoid, 29.8 × 17.3 (24–38 × 15–25) μm, and the sporocysts lanceolate, 22.6 × 5.4 (16–27 × 5–7) μm. Oocyst and sporocyst residua are present, but not a polar granule and a micropyle. The oocysts and sporocysts of E. microcapi are ellipsoid, measuring respectively 38.1 × 25.3 (35-41 × 23-26) μm and 18.1 × 7.4 (16-19 × 6–8) μm. Oocyst and sporocyst residua, a micropyle (mean 3 μm), and a distinct micropyle cap (2 μm high) are present, but not a polar granule. The oocysts of E. urodela are spheroid, 22.2 (14-26) μm, and the sporocysts lanceolate, 16.3 × 5.8 (12-19 × 4-7) μm. Oocyst and sporocyst residua are present, but a polar granule and a micropyle are absent.