新型冠状病毒肺炎疫情对高校微生物学教学带来的挑战与发展机遇

突如其来的新型冠状病毒肺炎疫情使得网上在线教学成为这段时间的唯一教学方式。这一方面给高校的广大师生提出了新的挑战,但同时也给近年来一直进行的高等教育开放式教育教学改革发展潮流按下了加速键。《微生物学通报》以"第十七届全国微生物学教学和科研及成果产业化研讨会"为契机邀稿组织出版的这期"高等院校教学主题刊",很好地反映了近年来在开放式教育形势下我国微生物学教学改革与人才培养的最新进展和发展态势,其中也有文章介绍了疫情期间选择和使用线上教学技术的经验。期望该主题刊的出版有助于进一步促进广大微生物学教师强化互联网意识,打造"互联网+"思维,重塑课堂教学形态,通过广大教师间的教改经验交流与合作,进一步促进我国微生物学课程建设水平与教学质量的全面提升。     

我国当代微生物学课程建设与教学改革研究进展——“高等院校教学专刊”序言

积极进行微生物学教学改革经验交流,对于提高高等院校微生物学教学水平和微生物学相关人才培养质量具有重要意义。为了反映我国当代微生物学课程建设与教学改革的最新进展和发展态势,《微生物学通报》以"第十五届全国微生物学教学和科研及成果产业化研讨会"大会为契机,邀约有微生物学及相关学科教学经验的高校教师撰写稿件,通过严格评审后择优选取文章,组织出版了这期"高等院校教学专刊",期望该专刊的出版有助于我国高校微生物学教师间的教改经验交流与合作。     

开放式教育潮流下的我国微生物学教学改革与人才培养

信息通信技术的迅猛发展不仅改变了知识的传播方式,也对高等教育的教学理念、教学模式和教学方法产生了深远的影响,以各类在线开放课程建设为代表的开放式教育理念目前已在高校中获得普遍的认可和实施。《微生物学通报》以"第十六届全国微生物学教学和科研及成果产业化研讨会"大会报告为主要稿源组织出版的这期"高等院校教学主题刊"很好地反映了在开放式教育潮流下我国微生物学教学改革与人才培养的最新进展和发展态势。期望该专刊的出版有助于进一步加强我国高校微生物学教师间的教改经验交流和合作,促进微生物学教学质量的全面提升。     

优化微生物学教学

优化微生物学教学杨文博（南开大学微生物学系,天津３０００７１）微生物学是生物学领域中一门重要的基础学科。学科的发展需要大批的研究人员,而高等院校则肩负着培养人才的重任。如何搞好微生物学教学,为国家输送合格的从事微生物学研究的人员是值得探讨的问题。本文...     

细菌分类学教学的几点体会

细菌分类学教学的几点体会杨文博（天津南开大学微生物学系,天津３０００７１）细菌分类学是微生物学一门重要的分支学科。在设置微生物学系或微生物学专业的一些高等院校按专业必修课开设这门课。笔者在多年从事细菌分类学的教学工作中,深得一些体会,草拟成文,愿与同...     

以“新冠”病毒肺炎疫情为案例的问题导向式微生物学课程思政教学设计

在微生物学课程中开展思政教学有助于提升相关专业学生的思想道德修养和综合素质,是当前高校教育"立德树人"根本任务的具体要求,也是思政教育"全过程、常态化"的重要体现。案例教学法是微生物学课程思政的一种重要教学方法,主要以微生物学科发展中的一些著名学者及其事迹为案例,引导学生认识和理解这些案例的思想内涵,以提升自身思想道德水平。该教学方法在实践中获得了较为理想的教学效果,但也存在着设计不够充分、时效性不足等问题。针对这些问题,本文提出了以新型冠状病毒肺炎(COVID-19,简称"新冠"病毒肺炎)疫情为案例的问题导向式微生物学课程思政教学设计方案。该设计基于当前"新冠"病毒肺炎疫情中涌现出的诸多先进人物和事迹,以及暴露出的一些不良现象和问题,通过将这些案例与微生物学专业知识,以及微生物学科发展历史上的经典人物事迹进行有机整合和提炼,开展问题导向式教学。这些案例都是学生亲身经历过的重大事件,因此能有效地提升学生的参与感,引发学生的共鸣。使用这些案例是对微生物学课程思政经典教学案例的有益补充,能更好地引导学生在学习相关专业知识的同时,主动思考各案例所蕴含的思想道德意义并将之内化为自己的价值信念,帮助他们塑造正确的"三观",最终实现微生物学课程思政"寓思想教育于科学知识学习"的教学目标。     

新时代背景下的兽医微生物学发展

2017年12月,《微生物学通报》首次与中国微生物学会兽医微生物学专业委员会合作推出“兽医微生物学主题刊”,集中刊登了兽医微生物学研究领域的病原分离鉴定、诊断方法、分子流行病学及兽用生物制品研发等方面的最新进展及成果。主题刊发表后引起了同行及读者的广泛好评。2019年末,突如其来的新型冠状病毒肺炎疫情给人类的生活、工作与学习带来了巨大影响,也让病毒、变异、核酸检测、疫苗等词汇快速进入大众视野。“同一健康”“公共卫生”“生物安全”在社会层面被广泛认知,兽医微生物学对公共卫生和人类健康的重要作用愈加突显。在这种背景下,时隔五年,《微生物学通报》与兽医微生物学专业委员会再次达成共识,联合推出“兽医微生物学主题刊”第二季,旨在系统梳理我国兽医微生物学研究领域的新理论、新技术与新产品,搭建兽医微生物学科研工作者学术思想与科研成果的交流与展示平台,推进学科发展与繁荣,为健康中国、健康世界贡献智慧与力量。     

中美课程教学差异分析及启示——基于食品专业“微生物学”视角

以中国南昌大学食品学院开设的"微生物学"和美国University of Minnesota食品科学与营养系的Introductory Microbiology为研究对象,从课程安排、教学过程、实践环节和知识考察等方面对食品专业"微生物学"课程教学进行对比研究,以此窥豹一斑。研究发现,国内高校"微生物学"课程存在教学内容更新滞后、课堂讨论互动不足、考查方式多元化欠缺等问题,学生学习存在投入时间偏少、知识点掌握不牢固、考试后遗忘较快、应用知识解决问题能力较差等问题。要更好地开展食品专业"微生物学"教学,必须以学生为中心,及时更新教材内容,结合现代技术开展启发教学、案例教学,有效建构学生知识体系,施行课程助理制度,完善考核制度,提升教师自身工程化能力,从而助推提升教学质量。     

高职教育食品微生物学教学改革初探

在高职教育中,食品微生物学是一门涉及范围广、涉及学科多、实践性很强、以与食品有关的微生物为主要研究对象的学科。根据食品微生物学课程的总体教学目标要求,结合当前该门课程在教学中存在的诸多问题,提出教学改革问题,以有效的提高食品微生物学课程的教学质量。     

成果导向教育理念(OBE)下的环境工程微生物学课程教学改革与实践

环境工程微生物学是环境类专业的学科基础课,该课程对学生的知识架构以及应用技能的培养起到了重要支撑作用。为了实现该课程定位目标,达到课程的学习预期,我们将成果导向教育理念(Outcomes-based education,OBE)引入到环境工程微生物学课程教学改革实践中,提出在环境工程微生物学课程教学中实施逆向设计、正向实施的原则,即根据课程定位制定环境工程微生物学的预期学习产出,在预期学习产出的基础上优化教学过程,如对教学内容进行取舍,增强环境工程微生物学与其他课程的协调性,在教学实施中强化学生的主体地位,通过教学方法的改革促成预期学习产出,构建合理的学习评价体系。尽管将OBE理念引入到教学实施中取得了一些成效,但该体系的建设还有待于进一步完善。     

壳聚糖酶的克隆表达与壳寡糖的制备分析

目的:克隆壳聚糖酶基因于大肠杆菌中实现高表达,制备壳寡糖。方法:以枯草芽孢杆菌总DNA为模板扩增壳聚糖酶基因(CSN),克隆至载体pET23a(+)上,转化菌株BL21(DE3)。重组子经0.5 mmol/L IPTG诱导后,SDS-PAGE和质谱检测与鉴定重组酶。酶纯化后水解壳聚糖,薄层色谱分析其水解产物。结果:质谱证明壳聚糖酶(31.5kDa)成功表达,表达量占菌体总蛋白的45%左右。纯化后重组酶浓度为900 mg/L,纯度95%、回收率85%,酶活力为10 000 U/mg。壳聚糖降解产物为壳二糖至壳四糖。结论:原核表达载体pET23a(+)-CSN构建正确,壳聚糖酶表达量与活性高,适用于水解壳聚糖制备壳寡糖。     

国内外蝗害治理技术现状与展望

本文首先概述了国内外蝗虫发生与为害的态势,总结了现阶段我国蝗虫发生与为害的主要特点:即农田飞蝗暴发频繁而且严重,草原土蝗的发生时常造成严重的经济损失,而且侵入城市干扰市民生活,我国与周边国家之间蝗虫过境迁移频繁,使用化学农药污染环境和农产品;分析了国内外蝗虫防治对策与技术的发展现状,重点介绍了应急防治和可持续治理对策、...     

Kinetics and thermodynamics of peroxidase- and laccase-catalyzed oxidation of N-substituted phenothiazines and phenoxazines

N -substituted phenothiazines (PTs) and phenoxazines (POs) catalyzed by fungal Coprinus cinereus peroxidase and Polyporus pinsitus laccase were investigated at pH 4–10. In the case of peroxidase, an apparent bimolecular rate constant (expressed as k _cat/K _m) varied from 1 ×10⁷M⁻¹s⁻¹to 2.6×10⁸M⁻¹s⁻¹ at pH 7.0. The constants for PO oxidation were higher in comparison to PT. pH dependence revealed two or three ionizable groups with pK _a values of 4.9–5.7 and 7.7–9.7 that significantly affected the activity of peroxidase. Single-turnover experiments showed that the limiting step of PT oxidation was reduction of compound II and second-order rate constants were obtained which were consistent with the constants at steady-state conditions. Laccase-catalyzed PT and PO oxidation rates were lower; apparent bimolecular rate constants varied from 1.8×10⁵M⁻¹s⁻¹ to 2.0×10⁷M⁻¹s⁻¹ at pH 5.3. PO constants were higher in comparison to PT, as was the case with peroxidase. The dependence of the apparent bimolecular constants of compound II or copper type 1 reduction, in the case of peroxidase or laccase, respectively, was analyzed in the framework of the Marcus outer-sphere electron-transfer theory. Peroxidase-catalyzed reactions with PT, as well as PO, fitted the same hyperbolic dependence with a maximal oxidation rate of 1.6×10⁸M⁻¹s⁻¹ and a reorganization energy of 0.30 eV. The respective parameters for laccase were 5.0×10⁷M⁻¹s⁻¹ and 0.29 eV. Received: 20 September 1999 / Accepted: 24 February 2000     

Coiled-coil nanomechanics and uncoiling and unfolding of the superhelix and alpha-helices of myosin

The nanomechanical properties of the coiled-coils of myosin are fundamentally important in understanding muscle assembly and contraction. Force spectra of single molecules of double-headed myosin, single-headed myosin, and coiled-coil tail fragments were acquired with an atomic force microscope and displayed characteristic triphasic force-distance responses to stretch: a rise phase (R) and a plateau phase (P) and an exponential phase (E). The R and P phases arise mainly from the stretching of the coiled-coils, with the hinge region being the main contributor to the rise phase at low force. Only the E phase was analyzable by the worm-like chain model of polymer elasticity. Restrained molecular mechanics simulations on an existing x-ray structure of scallop S2 yielded force spectra with either two or three phases, depending on the mode of stretch. It revealed that coiled-coil chains separate completely near the end of the P phase and the stretching of the unfolded chains gives rise to the E phase. Extensive conformational searching yielded a P phase force near 40 pN that agreed well with the experimental value. We suggest that the flexible and elastic S2 region, particularly the hinge region, may undergo force-induced unfolding and extend reversibly during actomyosin powerstroke.     

Synthesis of hapten and conjugates of coumestrol and development of immunoassay

3-O-Carboxymethylcoumestrol was prepared as the hapten for immunoassay by a partial alkylation of coumestrol with ethyl chloroacetate in acetone alkalized with potassium carbonate. 3-O-Ethoxycarbonylmethylcoumestrol was separated by column chromatography and finally was hydrolyzed with formic acid. 1H and 13C NMR data (APT, COSY, HMQC, and HMBC) revealed that the reaction was regioselective, as 3-O-ethoxycarboxymethylcoumestrol was the only monosubstituted derivative. The hapten was then conjugated to bovine serum albumin and used for immunization of rabbits. A radioimmunoassay (RIA) system was established based on the polyclonal antiserum and a 125I-labeled hapten-tyrosine methyl ester conjugate as the radioligand. Parameters of the RIA: sensitivity: 12 pg per tube, 50% intercept: 140 pg per tube, working range: 20-4000 pg per tube. The cross-reactivity of a panel isoflavonoid and lignan phytoestrogens was either negligible (e.g. formononetin 0.07%; biochanin A 0.06%) or not detectable at all. The major immunoreactive peak in HPLC fractions from an alfalfa extract had the same retention time as coumestrol standard and represented 94.8% of the signal. The remaining 5.2% of immunoreactivity was distributed between five minor peaks. We conclude that after the validation for particular matrices, the method will be a useful tool for analysis of coumestrol, especially in low volume and low concentration samples.     

白术同源四倍体的诱导和鉴定及其与二倍体过氧化物酶的比较

以白术（Atractylodes macrooephala Koidz.）二倍体组培苗为材料,对其四倍体诱导方法进行研究,共获得45个白术同源四倍体株系,为优良株系的选育提供了材料。此外,还分析比较了其中8个白术四倍体株系与二倍体的过氧化物酶同工酶（POD）的酶谱差异,发现四倍体各株系过氧化物酶同工酶谱比二倍体的均多了Rf0.310的谱带,且总过氧化物酶比活力也发生了很大改变,对探讨白术四倍体优良株系的生理生化机理具有一定的参考价值。     

Effect of soil salinity and water stresses on growth and content of nitrogen,chloride and phosphate of wheat and triticale

Summary Three wheats and one triticale were grown, up to flowering stage, in pots on calcareous soil adjusted to a range of salinities (S₁=3.5, S₂=6, S₃=8.5, and S₄=11 mmhos/cm, 20°C, soilpaste extract) by adding solution consisting of 3∶2∶1 of Na-, Ca- and Mg chlorides in chemical equivalent amounts. Moisture in the pots was kept at 100% (W₁), 40% (W₂) and 20% (W₃) of the available water. The vegetative growth, nitrogen and phosphate were affected by S and W treatments, chloride was affected only by S. The interaction S×W affected only dry weight. Varietal effect was observed between wheat as a group and triticale. Multiple quadratic regression equations of these properties on salinity and water revealed that the higher the available water the wider the range of tolerable salinity. Triticale was relatively more tolerant to water stress. Salinity increases Cl and decreases N, whereas water stress enhances N accumulation to a certain extent. However, in triticale at S₃ and S₄ the effect of water stress on N was overshadowed by the excessive salinity. This did not occur for the wheat (Florence). P trends were described. R² for P was low (0.7435–0.3603) which made interpretations rather difficult.     

放牧对牧草光合作用、呼吸作用和氮、碳吸收与转运的影响

研究放牧对草地植物生理活动的影响,对于揭示草地放牧演替的生理机制有重要意义.大量研究表明,家畜放牧对牧草光合作用、呼吸作用以及C和N吸收与转运的影响,可以分为生理伤害和生理恢复2个阶段.放牧通过改变草地冠层结构影响牧草光合作用,净光合作用速率短期内迅速下降,随着叶面积指数增加又逐渐上升,呼吸作用有相似的变化趋势.牧草放牧后再生长所需的C和N最初主要来自根系和留茬中的贮藏物质,此后随着牧草生长恢复逐渐由同化作用供给,C代谢与土壤N水平负相关.放牧后牧草生理活动变化与牧草遗传特性、种间竞争、家畜放牧特征、非生物环境等因素密切相关.