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Stable carbon and nitrogen isotope analysis was used to investigate the host-parasite trophic relationship between the parasitic isopod Ichthyoxenus japonensis and one of its freshwater fish host Carassius auratus auratus from Lake Fuxian, China. No significant differences in δ13C and δ15N were observed between the heterosexual pairs of I. japonensis in the same host. δ13C and δ15N of I. japonensis were significantly lower than those of its host fish, and the isotopic ratios of the isopod increased with the increase of host fish isotopic signatures. Unlike isotopic fractionation patterns generally observed among consumers and their diets, isopod parasite was 13C and 15N depleted relative to the muscle tissue of this host fish. Differential isotopic fractionation patterns in the isopod parasite and the fish may be attributed to differences in parasite and host metabolism. [ABSTRACT FROM AUTHOR]

Gloeostereum incarnatum has edible and medicinal value and was first cultivated and domesticated in China. We sequenced the G. incarnatum monokaryotic strain GiC-126 on an Illumina HiSeq X Ten system and obtained a 34.52-Mb genome assembly sequence that encoded 16,895 predicted genes. We combined the GiC-126 genome with the published genome of G. incarnatum strain CCMJ2665 to construct a genetic linkage map (GiC-126 genome) that had 10 linkage groups (LGs), and the 15 assembly sequences of CCMJ2665 were integrated into 8 LGs. We identified 1912 simple sequence repeat (SSR) loci and detected 700 genes containing 768 SSRs in the genome; 65 and 100 of them were annotated with gene ontology (GO) terms and KEGG pathways, respectively. Carbohydrate-active enzymes (CAZymes) were identified in 20 fungal genomes and annotated; among them, 144 CAZymes were annotated in the GiC-126 genome. The A mating-type locus (MAT-A) of G. incarnatum was located on scaffold885 at 38.9 cM of LG1 and was flanked by two homeodomain (HD1) genes, mip and beta-fg. Fourteen segregation distortion markers were detected in the genetic linkage map, all of which were skewed toward the parent GiC-126. They formed three segregation distortion regions (SDR1-SDR3), and 22 predictive genes were found in scaffold1920 where three segregation distortion markers were located in SDR1. In this study, we corrected and updated the genomic information of G. incarnatum. Our results will provide a theoretical basis for fine gene mapping, functional gene cloning, and genetic breeding the follow-up of G. incarnatum. [ABSTRACT FROM AUTHOR]

Starches from sixteen cassava germplasms harvested at the same time in the Hainan region were evaluated for their physicochemical and structural properties. The granule morphology of all the isolated cassava starch samples showed round, bell or oval shapes and exhibited the same A-type crystalline pattern. The crystallinity range was 26.6-30.8%. The selected cassava germplasms showed a wide variation in granule size distribution: The D[4,3] (the average particle size) ranged from 13.49 µm to 306.27 µm. The water absorption capacity (192.6-226.7%), oil absorption capacity (185.-0-216.9%) and transparency (6.8-16.5%) indices varied significantly among the cassava germplasms. However, the retrogradation rates of the cassava starch pastes increased rapidly during the first 1 h and then stabilized. The solubility of starch increased with the temperature. In addition, the FTIR (Fourier Transform Infrared Spectrometer) ratios of 1045/1022 cm-1 and 1022/995 cm-1 of the sixteen cassava starches varied in the range of 1.06-1.78 and 0.78-1.04, respectively. These results indicated that the granule size, relative crystallinity, degree of short-range order, water and oil absorption capacities, solubility and transparency of the cassava starches were greatly influenced by the variety of cassava, which could help in determining the advantages of these starches for applications in different food and nonfood industries. [ABSTRACT FROM AUTHOR]

Variations of bacterioplankton community composition were monitored during Microcystis spp. blooms in Lake Taihu using denaturing gradient gel electrophoresis (DGGE) of amplified DNA fragments from April through November in 2005. Two sampling sites were selected—one in Meiliang Bay and the other in the center of the western region of the lake. The average abundance of Microcystis spp. was higher in Meiliang Bay than in the lake center, while the bacterioplankton community diversity of Meiliang Bay was significantly lower than that of the lake center (P < 0.05). Comparison of DGGE profiles indicated that in Meiliang Bay bacterioplankton communities decreased in band richness and species diversity as Microcystis spp. abundance increased. In the lake center, DGGE band number and Shannon index reached their peaks when Microcystis spp. blooms declined. The Shannon diversity index for the bacterioplankton community was negatively correlated with the Microcystis spp. abundance (r = -0.53, P = 0.10). Changes in composition and biodiversity of the bacterioplankton community in the two regions of the lake were moderately correlated with Microcystis spp. bloom formations, which suggested a possible linkage between bacterioplankton community variations and phytoplankton blooms events. [ABSTRACT FROM AUTHOR]