红酵母属RY菌株形成类胡萝卜素的研究

分离的红酵母属（Rhodotorula）RY菌株形成的色素组成简单,石油醚可萃取到较纯的一种主要组分──红色的多烯类类胡萝卜素。该菌的培养条件为：葡萄糖2％,硫酸铵1％,酵母膏0．3％,添加2×10^－6mol／L核黄素,初始pH6．0,28℃,160r／min振荡培养72h。添加核黄素可以明显促进该菌类胡萝卜素的形成。     

Production of (S)-styrene oxide by recombinant Pichia pastoris containing epoxide hydrolase from Rhodotorula glutinis

A recombinant yeast Pichia pastoris carrying the gene encoding epoxide hydrolase (EH) of Rhodotorula glutinis was constructed and used for producing (S)-styrene oxide by enantioselective hydrolysis of racemic mixtures of styrene oxides. The EH gene was obtained by PCR amplification of cDNA of R. glutinis and integrated into the chromosomal DNA of P. pastoris to express EH under the control of AOX promoter. The recombinant yeast has a high hydrolytic activity toward (R)-styrene oxide as 358 nmol min⁻¹ (mg cell)⁻¹, which is about 10-fold higher than that of wild type R. glutinis. When kinetic resolution was conducted by the recombinant yeast at a high initial epoxides concentration of 526 mM that constitutes an epoxide–water two-liquid phase, chiral (S)-styrene oxide with an enantiomeric excess (e.e.) higher than 98% was obtained as 36% yield (theoretical, 50%) at 16 h.     

红酵母RY-4中虾青素的分离纯化研究

本文主要研究了红酵母RY-4菌株中天然虾青素的提取和纯化工艺。通过各种破壁提取方法的比较分析,得出了酸热法破壁丙酮提取为较经济理想的粗色素提取方法,提取的粗色素油中虾青素含量达51.7%。通过对各种柱层析条件的摸索研究,得出了以硅胶为吸附剂,Ⅴ(石油醚)∶Ⅴ(乙酸乙酯)混和液为洗脱剂梯度洗脱从粗色素油中分离纯化虾青素的方法,所得虾青素纯度达到97%。     

D-amino acid oxidase: structure,catalytic mechanism,and practical application

D-Amino acid oxidase (DAAO) is a FAD-dependent enzyme that plays an important role in microbial metabolism, utilization of endogenous D-amino acids, regulation of the nervous system, and aging in mammals. DAAO from yeasts Rhodotorula gracilis and Trigonopsis variabilis are used to convert cephalosporin C into 7-aminocephalosporanic acid, the precursor of other semi-synthetic cephalosporins. This review summarizes the recent data on the enzyme localization, physiological role, gene cloning and expression, and the studies on the enzyme structure, stability, catalytic mechanism, and practical applications.Translated from Biokhimiya, Vol. 70, No. 1, 2005, pp. 51–67.Original Russian Text Copyright © 2005 by Tishkov, Khoronenkova.     

深红酵母的化学数值分类学研究

对29株深红酵母(Rhodotorula rubra)的裂解气相色谱(PyGC)数据分别采用三种数值分析方法进行化学数值分类学研究。结果显示,不管是聚类分析、主分量分析还是Q型因 子分析,均能得到极为相似的分类结果,其中Q型因子分析效果最佳。通过数值分类学研究,29株深红酵母被划分成不同的四群,其中NKRlll不能与上述四群聚类,作者建议将该菌株从Rh. Rubra中分出,仍保留Rh. pilimanaE种名。     

海洋红酵母的研究进展

海洋红酵母富含氨基酸、维生素及类胡萝卜素等多种营养物质,有较好的耐盐性,是天然色素源、极具潜力的饲料蛋白和食品添加剂,具有很高的应用价值。概述了海洋红酵母的主要特性,总结了国内外海洋红酵母菌种、培养条件及工业应用等方面的研究进展及发展前景。     

圆红冬孢酵母基因编辑及天然产物合成的研究进展

圆红冬孢酵母(Rhodotorula toruloides)是一种能够天然合成多种类胡萝卜素和油脂的非模式酵母。该菌能够利用各种廉价原料,耐受甚至同化利用多种有毒木质纤维素水解副产物。目前,该酵母被广泛用于微生物油脂、萜烯类化合物、各种高价值酶、糖醇和聚酮化合物的生产研究。鉴于其广阔的工业应用前景,研究人员对其开展了多维度的理论和技术的探索,包括基因组、转录组、蛋白组、遗传操作平台等。本文着重阐述近年来圆红冬孢酵母的代谢工程和天然产物合成的研究进展,并展望其细胞工厂构建中面临的挑战和可能的应对决策。     

Phosphate uptake by the yeast, Rhodotorula rubra, and the green alga, Selenastrum capricornutum Printz, after phosphate additions to steady-state continuous cultures

Abstract We examined phosphate (P_i) uptake by two well-characterized microorganisms: a green alga ( Selenastrum capricornutum ) and a heterotrophic yeast ( Rhodotorula rubra ). Phosphate uptake was measured in dual- and single-species continuous cultures after perturbation of a phosphorus (P)-limited steady-state culture by additions of varying concentrations of P_i. We found that, under these conditions, both organisms had very high transport rates for P_i. The yeast was able to attain higher internal P concentrations than predicted from either steady-state or from P-starved batch culture data. Because the yeast was able to sequester and store P_i more efficiently than the alga under dilute P_i continuous culture conditions, co-existence of the two organisms was ultimately controlled by the concentration of carbon available for growth of the yeast.     

红酵母类胡萝卜素高产菌株的筛选及其发酵生理学条件研究

从数株红酵母中选出了1株产类胡萝卜素能力较强的红酵母RY－98（生物量,类胡萝卜素含量和产量分别为19．9g/L,334.8ug/g和6．7mg/L);研究了该菌株产类胡萝卜素的最适营养与环境条件,获得了最佳的发酵生理学条件;葡萄糖40g/L,(NH4)2SO4 10g/L,酵母膏3g/L,蕃茄汁2mL/L,花生油0.5mL/L,接种量30mLL初始pH6.0和通气量（培养基装置040ml/250mL:,在此初步优化的培养条件下,红酵母RY－98经72小时摇瓶发酵其生物量,类胡萝卜素含量和产量分别可达26．8g/L,386.9ug/g和10．4mg/L,依次比初筛中提高了34．7％,15．6％,和55．2％。     

胶红酵母JB401降解脱色三苯甲烷类染料

从烟梗中分离筛选得到1株能够对三苯甲烷类染料高效脱色的微生物,经ITS-5.8S rDNA分析鉴定为胶红酵母,命名为Rhodotorula mucilaginosa JB401。全波长扫描实验结果证实染料的脱色由胶红酵母降解结晶紫引起。为了提高R.mucilaginosa JB401脱色结晶紫的能力,通过单因素试验对R.mucilaginosa JB401的培养条件进行了优化,得出菌体生长24 h后以2%接种量接入初始pH为5的脱色培养基并在37℃摇床培养,可以取得最优脱色效果,此时脱色50、100和200 mg/L的结晶紫达到90%去除率分别需要3、6和14 h。此外,胶红酵母对温度和pH良好的适应性使其具有应用于工业废水处理的潜力。