Development and application of RAPD-SCAR markers to identify intra-species hybrids of industrial Saccharomyces cerevisiae

To overcome the drawbacks of protoplast fusion in industrial breeding, strain-specific molecular markers were applied to select hybrids of industrial Saccharomyces cerevisiae strains. Random Amplified Polymorphic DNA (RAPD) analysis was used to generate strain-specific RAPD markers for two industrial yeast strains, Z8 and Z9. For industrial and technical controls, two RAPD markers with non-coding regions were converted into stable Sequence Characterized Amplified Region (SCAR) markers. Hybrids of Z8 and Z9 were obtained by protoplast fusion in combination with SCAR markers and were found to increase ethanol production by 4.3–8.1%. Results suggested that protoplast fusion could be combined with RAPD-SCAR molecular markers and applied in industrial breeding instead of auxotrophic markers.     

The Loss of Genetic Diversity in Sichuan Taimen as Revealed by DNA Fingerprinting

Species endangerment often derives from the “endangerment” of genetic diversity, thus loss of genetic diversity is an important cause of species extinction. Since historical specimens were unavailable, previous studies mainly described the genetic diversity status in the current population rather than the loss of genetic variation over time. In this study, we collected samples during1998–1999 and obtained historical specimens from 1957 to 1958. Based on the two sets of fish, we determined the changes in genetic diversity of Sichuan taimen using DNA fingerprinting. The differences in genetic parameters between the present samples and historical taimens revealed their loss of genetic variation. As a result, the existing populations have lower viability, and proper management has to be implemented to preserve genetic diversity.     

Effects of genome duplication on phenotypes and industrial applications of Saccharomyces cerevisiae strains

Applied Microbiology and Biotechnology - Polyploidy is common in Saccharomyces cerevisiae strains, but the physiological and phenotypic effects of ploidy changes have not been fully clarified....     

链霉菌基因组及次生代谢研究进展

链霉菌属革兰氏阳性放线菌,具有复杂的生活周期和次生代谢途径,并产生大量具有重要价值的天然代谢物。本文概述了链霉菌基因组染色体的独特结构与次生代谢途径的研究进展,重点论述了利用基因组信息改造和调控链霉菌次生代谢途径的研究成果。后基因组时代的功能基因组研究使人类能深入了解链霉菌家族,对链霉菌进行更加合理高效的遗传操作,为提高具有重要价值的天然代谢物的产量和获得新代谢物创造更有利的条件。     

酵母HOG-MAPK途径

酿酒酵母Saccharomyces cerevisiae的高渗透性甘油促分裂原活化蛋白激酶(highos-molarity glycerol mitogen-activated protein kinase,HOG-MAPK)途径是高度保守的信号转导途径,很多方面和高等真核生物MAPK途径类似。该途径在高渗应激环境下控制信号转导和基因表达,是细胞生存所必需的。现对酵母HOG-MAPK途径的信号转导以及信号传递的专一性控制、HOG-MAPK途径各组分的亚细胞定位和基因表达调控机制进行综述。     

Isolation and identification of newly isolated antagonistic Streptomyces sp. strain AP19-2 producing chromomycins

A new antagonistic strain of actinomycete, designated AP19-2, was isolated from the feces of giant pandas inhabiting the Foping National Nature Reserve in China. Cultural characteristic studies strongly suggested that this strain is a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene of strain AP19-2 evidenced profound similarity (97-99%) with other Streptomyces strains. Two pure active molecules were isolated from a fermentation broth of Streptomyces sp. strain AP19-2 via extraction, concentration, silica gel G column chromatography, and HPLC. The chemical structures of the two related compounds (referred to as chromomycin A2 and chromomycin A3) were established on the basis of their Infrared spectra (IR), High Resolution Electrospray Ionization Mass Spectrometry (HR-ESI-MS), and Nuclear Magnetic Resonance (NMR) data, and by comparison with published data.     

丹顶鹤(Grus japonensis)东、西种群巢址选择的分异

丹顶鹤(Grus japonensis) 大陆种群以布列亚山-小兴安岭-张广才岭为界分为东、西两部分.2004～2005年,通过实地测量丹顶鹤东、西种群主要繁殖地的31处巢址的生境因子并进行统计学分析发现:丹顶鹤东、西种群巢址的芦苇密度、苇丛面积及巢距干扰源距离的差异显著(P﹤0.05);采用系统聚类分析的方法可将位于5 个保护区的丹顶鹤巢分成两类,且两类鹤巢分属东、西种群;丹顶鹤东、西种群巢址选择的分异不仅表现在单个生境因子的数量差别,还表现为群体采取不同的隐蔽对策;丹顶鹤东、西种群营巢对水深和芦苇高度的选择稳定一致.生境丧失作为外因通过丹顶鹤的"K生活史"特征起作用,导致丹顶鹤东、西种群的巢址选择具有群体特征.     

酿酒酵母耐热相关基因DNA片断的初探

对模板DNA、Mg2+的浓度以及PCR反应程序等因素进行了研究,得出了对酿酒酵母(Saccharomyces     

Bacillus tianmuensis sp. nov., isolated from soil in Tianmu Mountain national natural reserve, Hangzhou, China

In a project aiming to isolate strains with the ability to produce nonribosomal peptides, a Gram-negative, endospore-forming, rod-shaped strain, designated B5^T, was isolated from a soil sample collected from Tianmu Mountain national natural reserve in Hangzhou, China. Strain B5^T contained meso -diaminopimelic acid in the cell wall peptidoglycan. The major cellular fatty acids were anteiso-C_15:0 and iso-C_15:0. The DNA G+C content was 42.5 mol%. The phylogenetic analysis based on 16S rRNA gene sequence indicated that strain B5^T fell within the genus Bacillus , with highest sequence similarity values to Bacillus barbaricus DSM 14730^T (96.4%) and Bacillus macauensis JCM 13285^T (95.5%). The isolate, however, could be distinguished from Bacillus strains with validly published names by low 16S rRNA gene sequence similarity values, distinct phenotypic and chemotaxonomic characteristics. On the basis of these polyphasic evidences, it is demonstrated that the isolate B5^T represents a novel species of the genus Bacillus , for which the name Bacillus tianmuensis sp. nov. is proposed. The type strain is B5^T (=DSM 22111^T=CGMCC 1.8879^T).