Transgenic technology has been widely applied to crop development, with genetically modified (GM) maize being the world’s second-largest GM crop. Despite the fact that rhizosphere bacterial and fungal populations are critical regulators of plant performance, few studies have evaluated the influence of GM maize on these communities. Plant materials used in this study included the control maize line B73 and the mcry1Ab and mcry2Ab dual transgenic insect-resistant maize line 2A-7. The plants and soils samples were sampled at three growth stages (jointing, flowering, and maturing stages), and the sampling compartments from the outside to the inside of the root are surrounding soil (SS), rhizospheric soil (RS), and intact root (RT), respectively. In this study, the results of alpha diversity revealed that from the outside to the inside of the root, the community richness and diversity declined while community coverage increased. Morever, the different host niches of maize rhizosphere and maize development stages influenced beta diversity according to statistical analysis. The GM maize line 2A-7 had no significant influence on the composition of microbial communities when compared to B73. Compared to RS and SS, the host niche RT tended to deplete Chloroflexi, Gemmatimonadetes and Mortierellomycota at phylum level. Nitrogen-fixation bacteria Pseudomonas , Herbaspirillum huttiense , Rhizobium leguminosarum , and Sphingomonas azotifigens were found to be enriched in the niche RT in comparison to RS and SS, whilst Bacillus was found to be increased and Stenotrophomonas was found to be decreased at the maturing stage as compared to jointing and flowering stages. The nitrogen fixation protein FixH (clusters of orthologous groups, COG5456), was found to be abundant in RT. Furthermore, the pathogen fungus that causes maize stalk rot, Gaeumannomyces radicicola , was found to be abundant in RT, while the beneficial fungus Mortierella hyalina was found to be depleted in RT. Lastly, the abundance of G. radicicola gradually increased during the development of maize. In conclusion, the host niches throughout the soil-plant continuum rather than the Bt insect-resistant gene or Bt protein secretion were primarily responsible for the differential assembly of root-associated microbial communities in GM maize, which provides the theoretical basis for ecological agriculture.

This study was conducted to evaluate 35 natural flavonoids for their in vitro susceptibility against E. coli (ATCC 25922), Ps. aeruginosa (ATCC 27853), B. subtilis (ATCC 530) and Staph. aureus (ATCC 6538) in search of a potential broad‐spectrum antibiotic.

The extensive use of copper fungicides has resulted in significant non-target effects on soil microbial communities. However, the documented effects are often variable and contradictory, depending on the methods used to assess them. In this study, we examined the effects of copper accumulation in surface soils on microbial catabolic activity, active biomass and composition, and sensitive bacterial species. The community-level catabolic profiles (CLCPs) showed that both normal (50 mg CuSO4 kg−1 soil) and high dosages (tenfold rate) of CuSO4 significantly increased the catabolic diversity of gram-positive bacteria, while the high dosage increased the overall catabolic activity of gram-negative bacteria. The phospholipid fatty acid (PLFA) analysis showed that the high dosage reduced the biomass of gram-positive bacteria by 27% but did not affect that of gram-negative bacteria. In comparison, the normal and high dosages decreased the fungal biomass by 34% and 58%, respectively. Furthermore, 16S rRNA-denaturing gradient gel electrophoresis (DGGE) fingerprint revealed that more than two-thirds of identified bands belonged to gram-negative bacteria. Some Cu-resistant gram-negative bacterial genera, such as Actinobacterium, Pseudomonas, and Proteobacterium, were detected in the soil to which the high dosage of CuSO4 had been applied. In conclusion, an excess application of CuSO4 increased the catabolic diversity of gram-positive bacteria and induced resistance in gram-negative bacteria, whereas the active fungal community displayed a dosage-dependent response to CuSO4 and can thus be used as a sensitive indicator of copper contamination.

生物化学包括结构生物化学(以下简称生化)、代谢生物化学和分子生物学,其中代谢生化是最富有挑战性的部分.不论教师还是学生,教好或者学好这一部分的内容都不容易.据我所知,不少老师在讲代谢的时候,就是按照PPT上的内容,走马观花地把每一步反应念出来.试想这样的代谢生化课谁会喜欢?笔者在多年的生物化学教学实践中发现,如果将生化逻辑引入这一部分的教和学,一方面会大大提高教学效果,另一方面还会大大激发学生的学习兴趣.本文就以糖酵解、三羧酸循环和磷酸戊糖途径为例,深入剖析它们各自的生化逻辑,希望对同行们的代谢生化教学有所帮助.

每年全国各地都会有高校招募新的生物化学(以下简称"生化")老师.当你有一天成为一名大学生化老师的时候,一定要做好充分的心理准备,因为你要承担的这门课不好教.在学生口中,素有"生理生化,必有一挂"的传言.如何让自己最终成长为一名优秀的、让学生喜爱的生化老师并非易事.笔者在南京大学从教生物化学已有28年,自认为是一个优秀的并深受绝大多数学生喜爱的生化老师.本文将结合自己多年的从教经历,从多个方面与同行特别是年轻的同行分享自己成功的经验、窍门,以及一些失败的教训,希望对同行的生化教学有所启发和帮助.

Modern agriculture has gained significant economic benefits worldwide with the use of genetically modified (GM) technologies. While GM crops provide convenience to humans, their biosafety has attracted increasing concern. In this study, the Illumina MiSeq was used to perform a high-throughput sequencing of the V3-V4 hypervariable regions of 16S rRNA gene (16S rDNA) amplicons to compare the rhizosphere bacterial communities of the EPSPS/GAT dual transgenic glyphosate-tolerant soybean line Z106, its recipient variety ZH10, and Z106 with glyphosate application (Z106G) during flowering, seed filling, and maturing stages under field settings. At each of the three stages, the alpha and beta diversity of rhizosphere bacterial communities revealed no significant differences between ZH10, Z106, and Z106G. However, some bacterial taxa demonstrated a greater proportional contribution, particularly the nitrogen-fixing rhizobium Ensifer fredii, in the rhizospheric soil of Z106 at the seed filling and maturing stages, when compared to ZH10 and Z106G. The present study therefore suggests that the EPSPS/GAT dual transgenic line Z106 and exogenous glyphosate application have a minimal effect on the composition of the soybean rhizosphere bacterial community but have no impact on the structure of the rhizosphere microbial community during a single planting season.

生物数据库是储存生物信息的载体,其功能主要是对生物信息进行收集、归纳和整理.面对生物信息爆炸的时代,生命科学的研究和生产实践越来越离不开各类数据库.在生命科学基础课程生物化学的教学中,蛋白质的结构和功能是其中重要的知识环节.基于此,笔者在生物化学教学中,尝试在蛋白质一级结构部分首次引入数据库概念,在蛋白质高级结构部分进一步引导学生熟悉数据库工具,同时在酶学部分帮助学生提升综合运用数据库解决问题的能力,引导大学生逐步掌握生物相关数据库的使用.

糖类的化学本质是多羟基醛或多羟基酮,或是它们的聚合物或衍生物.还原糖一般是指能使弱氧化剂还原的糖类,例如,葡萄糖和果糖,而蔗糖、糖原和淀粉等则是非还原糖.二羟基丙酮是结构最简单的酮糖,但许多网站、论坛和部分文献提及二羟基丙酮属于非还原糖,对于它的还原糖属性,出现了一些争议.基于此,通过斐林反应实验,确认了二羟基丙酮是还原糖,同时提出了以此为基础升级生化教学实验的方案,供授课教师选用.

《生物化学》以生物体为对象,研究其生命的化学本质,是生命科学领域的核心课程.长期以来,由于生物化学课程知识点多、范围广和内容抽象,在一定程度上会影响学生学习的自信心,压抑其学习过程中的兴趣,致使学习的积极性不高.最近10～20年里,国外将科学(science)、技术学(technology)、工程学(engineering)及数学(mathematics)的教育与艺术学(arts),特别是与艺术学中的音乐结合实施教学,形成一种所谓的STEAM (STEM+Arts)策略,对STEM教育进行辅助,取得了不错的效果.基于以上情况,结合国内生物化学教学实际,笔者尝试将生物化学歌曲应用于课堂教学过程中,辅助教学.生物化学歌曲可以将抽象难懂的生物化学知识转变成悦耳动听的歌曲,在教学过程中能激发学生的学习兴趣,活跃课堂气氛,使学生在学习过程中爱上生物化学;在生物化学歌曲的创作过程中,能促进学生的思考创新,内化重点难点,使深奥的问题形象化;在学习过程中用歌声展现生物化学的魅力,让知识成为有趣的知识,让其成为有趣的学习者.本文介绍了国内生物化学歌曲发展壮大历程,结合具体实例从利用生物化学歌曲引入教学、理解生物化学内容、密切联系生活三方面评论了生物化学歌曲在辅助生物化学教学中的应用,并从歌词的改编、旋律的选择、歌曲的传唱、教学的设计等方面需要注意的问题进行讨论.

ISBN:978-7-04-055657-5定价:106.00元出版时间:2021年3月该书是南京大学杨荣武教授主编的《生物化学原理》第3版的简明版,重点介绍了生物化学的核心内容,具有脉络清晰、内容新、概念性强、简洁、易懂、有趣等特点.全书共20章,内容涉及结构生物化学、代谢生物化学和分子生物学...>>详细ISBN:978-7-04-055657-5定价:106.00元出版时间:2021年3月该书是南京大学杨荣武教授主编的《生物化学原理》第3版的简明版,重点介绍了生物化学的核心内容,具有脉络清晰、内容新、概念性强、简洁、易懂、有趣等特点.全书共20章,内容涉及结构生物化学、代谢生物化学和分子生物学的基本内容.每章包括引言、主题内容、知识框故事、即时自测题、思考题等,另配有丰富的数字课程资源,如小结、授课音视频、教学课件、拓展资源、自测题和思考题答案等.

生物化学(以下简称"生化")作为生命科学中最重要的一门基础专业课程,与其他所有自然科学课程一样,教师在教学时最重要的一点是保证所讲授的知识和内容的科学性,避免向学生传递任何科学性的错误,否则必然会导致以讹传讹.笔者在多年的生化教学实践中,一直以科学性为先,但很遗憾地发现一些同行在教学中却犯了一些科学性错误,这让学生很茫然.这些错误可能来自某些教材,也可能来自网络,还可能就来自授课者之前的老师.下面我想集中介绍我接触过的生化中多个典型的科学性错误,并进行剖析,希望将来同行中不再有人犯这些错误.

生物化学(以下简称生化)是一门在分子水平上研究生命现象及其规律的科学,但正是其看不见、摸不着的分子水平的特点让很多学生在学习的过程中,觉得抽象、复杂、晦涩、难懂,甚至无助,这大大挫伤了他们学习的积极性,也影响了教师的教学效果.因此,作为这门课的任课老师必须想尽一切方法来解决这样的问题,以激发学生学习生化的兴趣.笔者在多年的生化教学实践中,一直尝试用各种手段调动学生的学习兴趣,其中有一招就是进行"演示和互动".本文结合一些代表性的实例,介绍这些"演示和互动"活动是如何促进生化教学的.希望这些例子可以被同行们直接借用,用于生化教学,以共同提高生物化学的课堂教学水平,最终让学生受益.

Podophyllotoxin is a potent cytotoxic agent and serves as a useful lead compound for development of anticancer agents. Tubulin is known as an attractive target for drug discovery and cancer therapies. There are few studies on the treatment of breast cancer with podophyllotoxin and its derivatives targeting tubulin. Here, a series of novel aryl 1,3,4-oxadiazole/1,3,4-thiadiazole acid podophyllotoxin ester derivatives (D1-D16) were synthesized. Among these compounds, D9 exhibited excellent antiproliferation activity against MCF-7 cells (IC50=2.46 +/- 0.12 mu M). Furthermore, D9 caused cell cycle arrest at the G2/M phase and induced cell apoptosis. Confocal microscopy showed that D9 inhibited microtubule polymerization by causing cancer cell growth inhibition. Molecular docking results suggested D9 could bind to the active binding site of tubulin. In a mouse model, compound D9 suppressed malignant growth without causing significant toxicity to normal tissues. Our findings support the utility of D9 as a novel compound for the development of anticancer agent.

In this study, two soybean genotypes, i.e., aluminum-tolerant Baxi 10 (BX10) and aluminumsensitive Bendi 2 (BD2), were used as plant materials and acidic red soil was used as growth medium.The soil layers from the inside to the outside of the root are: rhizospheric soil after washing (WRH), rhizospheric soil after brushing (BRH) and rhizospheric soil at two sides (SRH), respectively.The rhizosphere bacterial communities were analyzed by high-throughput sequencing of V4 hypervariable regions of 16S rRNA gene amplicons via Illumina MiSeq.The results of alpha diversity analysis showed that the BRH and SRH of BX10 were significantly lower in community richness than that of BD2, while the WRH exhibited no significant difference between BX10 and BD2.Among the three sampling compartments of the same soybean genotype, WRH had the lowest community richness and diversity while showing the highest coverage.Beta diversity analysis results displayed no significant difference for any compartment between the two genotypes, or among the three different sampling compartments for any same soybean genotype.However, the relative abundance of major bacterial taxa, specifically nitrogen-fixing and/or aluminum-tolerant bacteria, was significantly different in the compartments of the BRH and/or SRH at phylum and genus levels, indicating genotype-dependent variations in rhizosphere bacterial communities.Strikingly, as compared with BRH and SRH, the WRH within the same genotype (BX10 or BD2) always had an enrichment effect on rhizosphere bacteria associated with nitrogen fixation.

“生物化学”在生命科学教育中处于基础和核心的位置,教学的信息量大、难度高.教师们一直在努力探讨和提高“生物化学”的教学效果.目前,在疫情影响下,理论课程转入线上教学,对这门课程的教学带来了新的挑战和契机.生物化学的本质是在分子层面上描述生命活动,因此,我们选用SARS-CoV-2这一相对简单的生命形式为线索,按照“结构生物化学”的教学进展,从蛋白质、核酸到酶、受体再到疫苗和药物发展步步推进,设计并践行了五步走的PBL(practice-based learning)的教学方案,并把教学的效果分享出来,与教学同行一起探讨和提高.

In the past thirty years, the biosafety of the aboveground part of crops, including horizontal gene transferal through pollen dispersal and hybridization, has been the focus of research; however, microbial communities in the underground part are attracting increasing attention. In the present study, the soybean root-associated bacterial communities of the G2-EPSPS plus GAT transgenic soybean line Z106, its recipient variety ZH10, and Z106 treated with glyphosate (Z106J) were compared at the seedling, flowering, and seed filling stages by high-throughput sequencing of the V4 hypervariable regions of 16S rRNA gene amplicons using Illumina MiSeq. The results obtained showed no significant differences in the alpha/beta diversities of root-associated bacterial communities at the three stages among ZH10, Z106, and Z106J under field growth conditions; however, the relative abundance of four main nitrogen-fixing bacterial genera significantly differed among ZH10, Z106, and Z106J. Ternary plot results indicated that in the root compartment, the proportional contributions of rhizobial nitrogen-fixing Ensifer fredii and Bradyrhizobium elkanii, which exhibit an extremely broad nodulation host range, markedly differed among the three treatments at the three stages. Thus, the present results indicate that transgenic G2-EPSPS and GAT soybean may induce different changes in functional bacterial species in soil, such as E. fredii and B. elkanii, from ZH10, which were compensated for/enriched at the flowering and seed filling stages, respectively, to some extent through as of yet unknown mechanisms by transgenic soybean treated with glyphosate.

生物化学是生命科学中最重要的基础专业课程之一.欲使教师讲好它,学生学好并非易事.在学生中经常流传着一句“生理生化,必有一挂”的口头禅,足见学生学习生物化学的难度.本文结合笔者在南京大学讲授生物化学25年多的实践及成功经验,与同行们分享生物化学的教学技巧和策略,如何上好第一次课,如何激发学生学习生物化学的兴趣,如何在教学中培养学生的科学思维,如何把传统课堂教学的手段与其他新型的教学方式结合,如何开展和组织“第二课堂”活动等,希望它们对同行们的生物化学教学有所启发和帮助.

Teaching biochemistry well is not an easy job for teachers and so is learning biochemistry well for students. Just as many students often complain, they virtually always fail in either physiology or biochemistry. I have been teaching biochemistry at Nanjing University for over 25 years and am very successful in my biochemistry-teaching career. The way and style that I teach biochemistry is highly praised by both my students and my fellow teachers. As an instructor, the most important thing is, I think, you have to do your best to arouse or ignite students' interest in biochemistry learning. But how? In this article, I will introduce many first-hand practical tips on how to arouse the students 'interest in studying biochemistry from giving the first lecture to last lecture, from how to combine advanced teaching methods with traditional teaching methods to how to combine classic biochemistry with latest biochemical developments, from the main classroom teaching to organization of extracurricular activities as the second classroom, and so on. These tips are proven very useful and then can be followed by other professors who are teaching biochemistry. Hopefully, they can help many professors improve their skills for teaching biochemistry.