姬菇原生质体制备与再生条件初探

目的探索姬菇(Pleurotus cornucopiae)菌丝原生质体制备和再生条件.方法以培养5d的幼嫩菌丝体为材料,在1.5%溶壁酶 0.5%纤维素酶混合酶作用下,以0.6mol/L甘露醇作渗透压稳定剂于pH5.5,30℃酶解2.5h,然后用血球计数板计数,计算原生质体产量.结果在上述条件下,原生质体产量达到3.12×107个/mL.原生质体适宜的再生培养基为马铃薯200g,蔗糖20g,酵母膏2g,KH2PO4 3.0g,MgSO4 ·7H2O 1.5g,维生素B1 0.1g,0.6mol/L甘露醇.采用上述培养基,原生质体再生率达到O.78%.为姬菇原生质体诱变及融合育种奠定了基础.     

平菇原生质体制备与再生条件初探

平菇原生质体制备最佳条件是菌丝培养5 d、酶浓度1.5%、pH 5.5、0.6 mol/L甘露醇渗透压稳定剂、酶解温度30℃、酶解时间2 h、OS培养基。原生质体过滤、纯化、稀释后涂布再生培养基,再生率为2.6%。     

滑菇原生质体制备研究

通过对滑菇原生质体最佳制备条件的研究表明:利用OS培养基、1.5%溶壁酶将培养13 d的滑菇菌丝在0.6 mol/L甘露醇、pH 6.5、25℃条件下酶解5 h,原生质体产量最高,可达4.85×106个/mL。     

秀珍菇单孢子菌株原生质体制备条件的优化

以秀珍菇单核菌丝为材料,用溶壁酶进行原生质体的制备,考察各因素对原生质体产量的影响,用单因素试验和正交试验确定最佳条件。结果表明,菌龄为8 d菌丝体,0.6 mol/L甘露醇+10 mmol/L Tris-HCl为稳渗剂,酶解温度29℃、酶浓度1.6%的条件下酶解160 min。原生质体产量达到3.5×10~7 CFU/m L,原生质体再生率达到1.4%。     

影响枯草芽胞杆菌和荧光假单胞菌原生质体再生的因素

目的：为了提高再生率,对影响革兰阳性菌枯草芽胞杆菌KR株和革兰阴性菌荧光假单胞菌B13株原生质体再生的因素进行研究。方法：研究了酶解时间,再生方式,再生培养基中稳定剂的种类,Ca^2＋、Mg^2＋、琥珀酸钠、L-色氨酸的浓度及培养基的放置时间对KR和B13株原生质体再生的影响。结果：对KR株酶解20min,采用夹层培养,再生培养基中加入0.6mol/L蔗糖、0.03mol/L Ca^2＋、0.02mol/L Mg^2＋、0.3mol/L琥珀酸钠、0.2mol/L L-色氨酸,培养基在37℃放置72h,原生质体再生率可达42.7%;对B13酶解15min,采用夹层培养,培养基中加入0.6mol/L NaCl、0.02mol/L Ca^2＋、0.01mol/L Mg^2＋、0.3mol/L琥珀酸钠、0.1mol/L L-色氨酸,培养基在37℃放置48h,原生质体再生率可达15.3%。结论：影响革兰阳性菌枯草芽胞杆菌KR株和革兰阴性菌荧光假单胞菌B13株原生质体再生的因素是不同的。     

竹黄菌原生质体的制备与再生分析

为了提高竹黄菌(Shiraia bambusicola P.Hennings)中原生质体用于遗传转化时的转化效率,研究竹黄菌原生质体制备及再生的最佳条件,建立竹黄菌原生质体的高效遗传转化体系。本研究以竹黄菌为材料,采用正交试验分析方法,对影响竹黄菌原生质体制备及再生的主要因素,不同酶解时间、酶解温度、渗透压稳定剂及菌龄、不同再生培养基等进行了系统的研究。结果表明,以0.6 mol/L Na Cl为稳渗剂,用组合酶(质量分数1%裂解酶和质量分数1.5%崩溃酶按4:6体积比混合)在33℃条件下对菌龄为6 d的菌丝体酶解2 h,原生质体产量最高,达到10.57×10~6个/m L;以0.6 mol/L蔗糖为稳渗剂,用组合酶(质量分数1%裂解酶和质量分数1.5%崩溃酶按4:6体积比混合)在29℃条件下对菌龄为4 d的菌丝体酶解2 h,原生质体再生率最高,为0.293%;最适合竹黄菌原生质体再生的培养基是TB3再生培养基。     

羊肚菌原生质体制备与再生*

羊肚菌原生质体制备的最佳条件为以培养3d的菌丝体为材料,0.6mol/L蔗糖溶液为稳渗剂,1.5%浓度的溶壁酶30℃条件下酶解3个小时,可得原生质体产量最高为3.35×106个/100mg.以0.6mol/L的蔗糖溶液做稳渗剂,CYM再生培养基上得到原生质体再生率为0.171%.这一研究结果为羊肚菌通过原生质体技术进行菌株的遗传改良提供了重要技术参数.     

杏鲍菇原生质体制备与再生条件初探

研究酶浓度、酶解时间、酶解温度、培养时间、稳渗剂种类、pH值和几种再生培养基对杏鲍菇原生质体制备与再生的影响。最适条件为 :在 30℃、pH5 .5、1.5 %溶壁酶条件下 ,以 0 .6mol L甘露醇作为稳渗剂 ,酶解 2 .5h ,原生质体产量达到 2 .90× 10 7个 mL。将所得原生质体过滤、纯化、稀释后涂布再生培养基 ,再生率为 0 .18%。为利用原生质体技术进行杏鲍菇育种奠定了基础。     

丝状真菌AL18的原生质体制备和再生条件的优化

目的:为了建立起产苝醌类光敏剂丝状真菌AL18原生质体制备和再生体系。方法:采用单因素实验法研究了预处理方式、渗透压稳定剂和酶解条件对原生质体制备率和再生率的影响。结果:原生质体制备及再生的最佳条件是用0.3%的β-巯基乙醇预处理15 min,酶解液以0.6 mol/L的MgSO4·7H2O作为渗透压稳定剂,0.02 mol/L的磷酸盐缓冲液pH值为5.8,纤维素酶:蜗牛酶=2:3,酶的总浓度为15mg/mL,36℃酶解2h;以0.6mol/L的蔗糖作为再生培养基的渗透压稳定剂。结论:原生质体的制备率和再生率可分别达到1.42×107/mL和3.2%。     

赤芝原生质体分离与再生研究

以赤芝(Ganoderma lucidum)为供试菌种,研究了不同酶解温度、酶解时间、渗透压稳定剂浓度及菌龄、再生培养基等对赤芝菌丝的原生质体制备与再生的影响。结果表明:菌龄为4 d的菌丝,以0.4 mol/m L的甘露醇作渗透压稳定剂配制成浓度为0.02 g/m L的溶壁酶,于p H 5.0、25℃条件下酶解2.0 h,其原生质体数最高可达3.87×107/m L,MYG再生培养基上再生率达到0.016%。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.