Spatio-temporal variability of phytoplankton assemblages and its controlling factors in spring and summer in the Subei Shoal of Yellow Sea, China

The Subei Shoal is a special coastal area with complex physical oceanographic properties in the Yellow Sea.In the present study,the distribution of phytoplankton and its correlation with environmental factors were studied during spring and summer of 2012 in the Subei Shoal of the Yellow Sea.Phytoplankton species composition and abundance data were accomplished by Utermohl method.Diatoms represented the greatest cellular abundance during the study period.In spring,the phytoplankton cell abundance ranged from 1.59×10^3 to 269.78×10^3 cell/L with an average of 41.80×10^3 cell/L,and Skeletonema sp.and Paralia sulcata was the most dominant species.In summer,the average phytoplankton cell abundance was 72.59×10^3 cell/L with the range of 1.78×10^3 to 574.96×10^3 cell/L,and the main dominant species was Pseudo-nitzschia pungens,Skeletonema sp.,Dactyliosolen fragilissima and Chaetoceros curvisetus.The results of a redundancy analysis(RDA)showed that turbidity,temperature,salinity,pH,dissolved oxygen(DO),the ratio of dissolved inorganic nitrogen to silicate and SiO4-Si(DIN/SiO4-Si)were the most important environmental factors controlling phytoplankton assemblages in spring or summer in the Subei Shoal of the Yellow Sea.

Karyological observations of Ulva linza chromosomes

Abstract Ulva linza is one of the species that causes green tides in the Yellow Sea,China.Due to the diffi culties in chromosomal preparation,the large numbers of chromosomes,and their relatively small sizes,there have been no reported studies on Ulva macroalgae chromosomes.The karyotypes and chromosomes in U.linza were observed after a series of treatments.The chromosomes were pretreated with 0.1%colchicine for 12 h and then mixed with enzymes.The samples were dropped from 30 cm height onto glass slides,which spread out the surface coat.These pretreatments were the optimal chromosomes preparation treatments.The prepared chromosomes were stained with 4',6-diamidino-2-phenylindole(DAPI),which is a fl uorescent probe sensitive and specifi c to DNA.The chromosome number in the haploid male and female gametophytes was n=9,and was 2 n=18 in the diploid sporophytes.The female gametophyte chromosomes were between 0.804 and 2.292μm in size,the male gametophyte chromosomes were between 0.917 and 2.916μm,and the sporophyte chromosomes were between 0.912 and 2.167μm.The relative sizes of the chromosomes were used to analyze the karyotypes of the female and male gametophyte chromosomes.The results provide a solid foundation for the basic technique that can be used to localize molecular markers of Ulva chromosomes.

Large scale preparation of phycobiliproteins from <i>Porphyra yezoensis</i>using co-precipitation with ammonium sulfate

The purpose of this study was to extract phyco-biliproteins (PBP) from Porphyra yezoensis using an optimized procedure and further establish a large scale process for protein production. According to our previous experiences on the extraction of PBP, salting out methods, e.g. ammonium sulfate precipitation, worked more efficiently than isoelectric precipitation, differential centrifugation or ultrafiltration. Thus, we chose ammonium sulfate to coprecipitate PBP in crude solution. After four times of precipitation followed by one time of high speed centrifugation, the maximum purity of crude phycoerythrin and phycocyanin reached 1.94 (A565/A280) and 0.85 (A615/A280), with a yield of 0.50% and 0.37%, respectively. A total of 0.94 mg phycoerythrin and 0.54 mg phycocyanin with purity of more than 3.2 were obtained from 1 g dried P. yezoensis after additional chromatography. We further scaled up the frozen dried P. yezoensis from 20 g to 400 g, with 1295 mg phycoerythrin and 593 mg phycocyanin obtained.

Advances in the study of tegument protein VP26 in white spot syndrome virus

White spot syndrome virus(WSSV)has become one of the most widespread causes of mortality in commercial shrimp farming due to its broad host range,rapid spread and high lethality.The tegument protein VP26,which is loosely connected to nucleocapsid and envelope,is one of the major proteins of WSSV and has an important role in the initial stages of viral infection.Recent research has emphasized the vp26 gene,the structure of the VP26 protein,and VP26 binding proteins.Such knowledge is required to develop VP26 immune adjuvant to control WSSV.This paper reviews the related research of VP26 to provide reference for the prevention and treatment of WSSV.

微藻规模化培养研究进展

微藻作为地球上最古老的物种之一,其诞生可追溯到35亿多年前。微藻的种类十分丰富,形态也多种多样。微藻一般都含有叶绿体,因此可进行光合作用,有研究表明微藻固定CO2的能力是陆地植物的10倍。微藻以其丰富的代谢产物及独特的生理特性在可再生能源、生物医药、食品工业和环境监测等方面有着广泛的应用。然而如何在控制成本的前提下对微藻进行规模化培养成为困扰微藻应用行业的一大难题。为此,本文将从微藻的生化特点及其在各领域中的应用、微藻的规模化培养和微藻的采收3个方面对微藻的规模化培养近十年的研究进展进行综述,旨在为微藻高效培养、低成本采收的研究开发提供参考。

橙色荧光蛋白的研究进展及其应用

荧光蛋白(Fluorescent protein,FPs)可作为探针用以探究细胞内分子间相互作用,追踪特定代谢物的代谢途径,对活细胞内的各种代谢过程和细胞通路进行详细、准确的描述。目前已有的FPs几乎已经覆盖了从紫外光到远红外光的所有光谱波段,这些FPs借助高分辨率显微技术应用于生命科学的诸多领域,为生物学的发展作出巨大贡献。橙色FPs通常指光谱区间在540–570nm的FPs,近几年来关于橙色FPs的研究进展较快,并且其作为标记蛋白以及荧光共振能量转移技术(Fluorescence resonance energy transfer,FRET)中的荧光受体在生物学及医学领域得到较多的应用。文中综述了近15年橙色FPs领域的相关研究,重点聚焦橙色FPs的发展和应用,为今后橙色FPs的研究提供依据。