Anatomy and lignin deposition of stone cell in Camellia oleifera shell during the young stage

Protoplasma - As the by-products of edible oil production with rich lignin, the reserves of Camellia oleifera shell were abundant and had a great economic value. Lignin was the most important...     

Astragaloside IV alleviates atherosclerosis through targeting circ_0000231/miR-135a-5p/CLIC4 axis in AS cell model in vitro

Molecular and Cellular Biochemistry - Non-coding RNAs (ncRNAs) have shown to act as crucial mediators in atherosclerosis (AS) development. The purpose of our study was to explore the role of...     

超分子多肽自组装在生物医学中的应用

近年来,自组装多肽纳米技术因其可形成规则有序的结构、具有多样的功能而备受关注。研究发现自组装多肽能在特定的条件下形成具有确定结构的聚集体,这种聚集体具备生物相容性好、稳定性高等优点,表现出不同于单体多肽分子的特性和优势,因此其在药物传递、组织工程、抗菌等领域具有良好的应用前景。文中介绍了自组装多肽形成的分子机理、类型、影响因素,综述了自组装多肽形成的纤维肽基水凝胶与自组装抗菌肽的最新进展,并提出目前多肽自组装技术所存在的问题及展望。     

Streptomyces luteolifulvus sp. nov., a novel actinomycete isolated from soil in Nanjing,China

During the investigation of exploring potential sources of novel species and natural bioactives, a novel actinomycete, designated strain HIT-DPA4^T, was isolated from a soil sample, which was collected from Nanjing, Jiangsu Province, PR China and characterized using a polyphasic approach. On the basis of 16S rRNA gene sequence similarities and the result of phylogenetic analysis, strain HIT-DPA4^T was most closely related to Streptomyces cyaneus CGMCC 4.1671 ^T, and shared the highest sequence similarity of 98.76%. In addition, the cell walls of the species HIT-DPA4^T contained LL-diaminopimelic acid as the diagnostic diamino acid and the whole-cell hydrolysates were identified as glucose and ribose, and the principal phospholipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and phosphatidylmonomethylethanolamine. MK-9(H₆) and MK-9(H₄) were predominant menaquinones; and C_16:0, anteiso-C_15:0 and C_15:0 as major cellular fatty acids of the organism HIT-DPA4^T. Gene Ontology database analysis and antiSMASH server predicted results displayed that strain HIT-DPA4^T was a promising classification units, which has various types of functions and contains multiple biosynthetic gene clusters with the similarity more than 80%. Multilocus sequence analysis (MLSA) of five housekeeping genes (atpD, gyrB, recA, rpoB and trpB) illustrated that Streptomyces luteolifulvus formed a separate branch in the genus Streptomyces. However, a combination of low level of DNA-DNA relatedness and physiological properties indicated that strain HIT-DPA4^T can be distinguished from its phylogenetically related species Streptomyces cyaneus CGMCC 4.1671 ^T. Moreover, gene synteny research could be further differed organism HIT-DPA4^T from similarity species. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces luteolifulvus sp. nov. is proposed. The type strain is HIT-DPA4^T (=?CGMCC 4.7558 ^T?=?TISTR 2751 ^T).

     

Consumer-driven nutrient release to the water by a small omnivorous fish enhanced ramet production but reduced the growth rate of the submerged macrophyte Vallisneria denseserrulata (Makino) Makino

Small fish are highly associated with submerged macrophytes but may potentially hamper their growth due to nutrient excretion that stimulate growth of phytoplankton and periphyton growth. We conducted a mesocosm experiment to elucidate the effects of the small omnivore Chinese bitterling Acheilognathus macropterus on the growth of phytoplankton, periphyton and the submerged macrophyte Vallisneria denseserrulata. The treatments were fishless as well as low (LF) and high (HF) fish density. We found that the concentrations of nutrients and the phytoplankton biomass increased substantially in both fish treatments, leading to a significantly higher light attenuation compared with the control. Moreover, bitterling substantially enhanced the biomass of periphyton on plant leaves. Consequently, the relative growth rate (RGR) of V. denseserrulata was significantly suppressed in HF, while RGR in the LF treatment did not differ significantly from the controls. However, the bitterling also stimulated the ramet production of V. denseserrulata, significantly. Our results indicate that Chinese bitterling reduce the RGR of V. denseserrulata under high fish density condition. Therefore, the density of Chinese bitterling should be kept low in order to reduce the negative effects of the fish on the RGR of submerged macrophytes (e.g. V. denseserrulata), when restoring lakes by plant transplantation.

     

琉球病毒、索尔韦齐病毒、苏里斯病毒等三种沙粒病毒实时荧光RT-PCR检测方法研究

建立可检测琉球病毒(Ryukyu virus,RYKV),索尔韦齐病毒(Solwezi virus,SOLV)以及苏里斯病毒(Souris virus,SOUV)等三种沙粒病毒的实时荧光定量RT-PCR检测方法.分析三种病毒流行病学分布特征,从国际公共数据库搜索下载基因组序列,进行比对分析,确定检测靶标,借助primer premier 6.0生物信息学软件,设计引物和探针,建立实时荧光定量RT-PCR检测方法,利用化学合成和体外转录方法制备模拟样本,比较评价三种方法的检测限、特异性、重复性特征.所建实时荧光定量RT-PCR检测方法均可有效扩增检测病毒RNA靶标,检测限分别为40拷贝/μL、7拷贝/μL和15拷贝/μL,检测汉城病毒、汉滩病毒、登革病毒Ⅰ～Ⅳ型分离株、发热伴血小板减少综合病毒及30份健康人血清样本无非特异性扩增,三种病毒相互间以及其他8种出血热相关沙粒病毒RNA间无交叉反应,重复性比较分析显示变异系数均在2％以内.本研究建立的检测RYKV、SOLV和SOUV三种沙粒病毒的实时荧光RT-PCR方法具备用于相关疑似感染者临床样本、宿主动物标本以及进出口物品的筛查检测的潜力,但因未经基于实际病毒感染样本的比较评价,检测结果的解释仍具有一定的局限性.     

Sustainability of SARS-CoV-2 Induced Humoral Immune Responses in COVID-19 Patients from Hospitalization to Convalescence Over Six Months

Virologica Sinica - Understanding the persistence of antibody in convalescent COVID-19 patients may help to answer the current major concerns such as the risk of reinfection, the protection period...     

Extensive profiling of the expressions of tRNAs and tRNA-derived fragments (tRFs) reveals the complexities of tRNA and tRF populations in plants

Evidence is emerging that t RNA-derived fragments(t RFs) are regulatory molecules. Studies of t RFs in plants have been based on conventional small RNA sequencing, and focused on profiling of t RF-5 and t RF-3 species. A more comprehensive and quantitative analysis of the entire t RF population is highly necessary. Here, we employ t RNA-seq and YAMAT-seq, and develop a bioinformatics tool to comprehensively profile the expressions of t RNAs and t RFs in plants. We show that in Arabidopsis,approximately half of t RNA genes are extremely weakly expressed, accounting for only 1% of total t RNA abundance, while～12% of t RNA genes contribute to ～80% of t RNA abundance. Our t RNA sequencings in various plants reveal that t RNA expression profiles exhibit a cross-species conserved pattern. By characterizing the composition of a highly heterogeneous t RF population, we show that t RNA halves and previously unnoticed 10–16-nt tiny t RFs represent substantial portions. The highly accumulated 13-nt and 16-nt tiny t RFs in Arabidopsis indicate that tiny t RFs are not random t RNA degradation products. Finally,we provide a user-friendly database for displaying the dynamic spatiotemporal expressions of t RNAs and t RFs in the model plants Arabidopsis and rice.     

一株中温淀粉酶菌株的分离鉴定及其产酶条件分析

利用固体淀粉筛选培养基,从安阳市郊区面粉厂附近的土壤里分离筛选出1株产淀粉酶的菌株,编号为MF-3-2.经过菌株形态、革兰氏染色、16S rDNA鉴定及系统进化树分析,初步确定其为枯草芽孢杆菌(Bacillus subtilis).摇瓶培养后对其酶学性质研究发现,该菌株淀粉酶的最适温度为65℃,最适pH值为6.0,在pH值4.8～6.0范围内仍能残余70％以上的酶活力.该菌株的最适生长温度为40℃,最适生长pH值为6.5.产酶条件优化结果表明:最适碳源为马铃薯淀粉,最适氮源为豆粕粉,最适碳氮比为1∶15,发酵温度30℃,发酵pH值6.0,装液量10％,种龄10h,接种量5％,转速200 r/min,48 h达到产酶高峰.通过发酵产酶条件优化,其淀粉酶活性达到86.8 U/mL,是优化前的35倍.另外,在酸性条件下还具有较好的活性.因此,该菌株的淀粉酶具有潜在的工业应用前景.     

Is oral microbiome of children able to maintain resistance and functional stability in response to short-term interference of ingesta?

Dear Editor, A series of studies had focused on the ecological stability of human microbiome (Lozupone et al.,2012;Faith et al.,2013;Moya and Ferrer,2016).Despite the continuous perturbation and the highly personalized composition within the human microbiome (Human Microbiome Project,2012),healthy adults stably maintain their microbial communities in terms of space and time (Faith et al.,2013;Moya and Ferrer,2016;Oh et al.,2016).This stability is proved to be critical for the well-being of human body (Lozupone et al.,2012).On the contrary,major shifts in microbial community composition are often related to diseases (Lynch and Pedersen,2016).