Proteomic and Genomic Analyses of Antimony Resistant Leishmania infantum Mutant

Background

Antimonials remain the primary antileishmanial drugs in most developing countries. However, drug resistance to these compounds is increasing and our understanding of resistance mechanisms is partial.

Methods/Principal Findings

In the present study, quantitative proteomics using stable isotope labelling of amino acids in cell culture (SILAC) and genome next generation sequencing were used in order to better characterize in vitro generated Leishmania infantum antimony resistant mutant (Sb2000.1). Using the proteomic method, 58 proteins were found to be differentially regulated in Sb2000.1. The ABC transporter MRPA (ABCC3), a known marker of antimony resistance, was observed for the first time in a proteomic screen. Furthermore, transfection of its gene conferred antimony resistance in wild-type cells. Next generation sequencing revealed aneuploidy for 8 chromosomes in Sb2000.1. Moreover, specific amplified regions derived from chromosomes 17 and 23 were observed in Sb2000.1 and a single nucleotide polymorphism (SNP) was detected in a protein kinase (LinJ.33.1810-E629K).

Conclusion/Significance

Our results suggest that differentially expressed proteins, chromosome number variations (CNVs), specific gene amplification and SNPs are important features of antimony resistance in Leishmania.     

Transport of Glutamate and Glutamine in the Light Leaf Spot Pathogen Pyrenopeziza brassicae

The kinetics of glutamic acid and glutamine uptake in the light leaf spot fungus, Pyrenopeziza brassicae , are biphasic. At low and high concentrations, glutamic acid and glutamine share a high-affinity and a low-affinity carrier, respectively, with K_ms of 4.0 and 4.4 μ m for uptake of glutamic acid and glutamine, respectively, by the high-affinity system, and K_m s of 580 and 560 μ m for uptake of glutamic acid and glutamine by the low-affinity system. The data suggest that glutamic acid and glutamine are taken up by a different system to that responsible for the uptake of ornithine, arginine, lysine and asparagine, and may represent system IV described in Neurospora crassa for the uptake of acidic amino acids.     

海南菠萝一种叶斑病病原菌的分离与鉴定及多基因序列分析

为明确菠萝叶斑病病原菌可可毛色二孢菌在海南省各市县的亲缘关系及遗传差异,从海南省的海口、澄迈、儋州、三亚、保亭等16个市县进行病样采集和病样分离,根据科赫氏法则鉴定,获得42株病原菌.观察形态特征,并基于多基因联合序列分析其遗传多样性.结果 表明,通过形态学鉴定和ITS与TUB2基因序列联合进化树分析发现,其中来自海口、澄迈、儋州、三亚、保亭等16个市县的16株代表病原菌均鉴定为可可毛色二孢菌(Lasiodiplodia theobromae),其分生孢子平均大小为(22.06～31.07) μm× (11.77～16.48) μm;通过ITS、TUB2、EF-1α、GAPDH、CHS-1和ACT基因拼接序列聚类分析,结果分为3个类群,海南岛的中部(儋州,昌江,白沙,五指山,万宁,琼海等地)聚为一个类群,中北部(屯昌,临高)聚为一个类群,西南部(东方,乐东,三亚等地)聚为一个类群.该结果说明来源于不同产地不同菠萝品种上的可可毛色二孢菌遗传多样性丰富,在海南省16个市县菠萝叶斑病菌中可可毛色二孢菌L.theobromae为优势种.     

Correction to: Dynamic Host Immune and Transcriptomic Responses to Respiratory Syncytial Virus Infection in a Vaccination-Challenge Mouse Model

Virologica Sinica - A correction to this paper has been published: https://doi.org/10.1007/s12250-021-00418-3     

Population Dynamics of Sugar Beets, Rhizoctonia solani, and Laetisaria arvalis: Responses of a Host, Plant Pathogen, and Hyperparasite to Perturbation in the Field

Rhizoctonia solani causes crown rot of sugar beets, a severe disease that has destroyed up to 60% of the plants in a test field in western Nebraska. Laetisaria arvalis, a natural hyperparasite of Rhizoctonia spp., was isolated from fields in western Nebraska. To test for the potential for biological control of R. solani, in November 1980 (following harvest) we applied various combinations of a nematicide (Telone II; Dow Chemical Co.), a nutrition source (sugar beet pulp), and an inoculum of L. arvalis in a randomized block design. Populations of R. solani, L. arvalis, and sugar beets were monitored monthly through October 1981 (just after harvest). In control and nematicide plots, the R. solani population did not change significantly through time. In plots inoculated with L. arvalis, the R. solani populations declined through March, concomitant with an increase in L. arvalis. L. arvalis then declined with a corresponding increase in the R. solani populations. Beet plant numbers declined significantly in all treatments. We suggest that reduction of the R. solani populations with the hyperparasite L. arvalis is possible but that a stable equilibrium naturally exists.     

瓜类果斑病菌的检测与防治进展

瓜类果斑病菌可引起西瓜、甜瓜等葫芦科植物患病,可通过种子远距离传播,是一种常见的瓜类采后果实腐烂的病原菌。该病害具有发病迅速、传播速度快等特点,一旦感染会对瓜类产量带来巨大损失,因而田间病菌的检测与诊断及早期预防十分重要。本文系统地综述了国内外瓜类果斑病菌的免疫学检测方法、分子生物学检测方法及防治等研究进展。     

丙型肝炎病毒多表位抗原在恒河猴中的免疫应答及保护性试验

利用HCV抗原多表位来研制HCV疫苗是目前的一个新方向.本研究利用HCV的HCV的5个保守表位串联,并加入破伤风类毒素上的一个T细胞激活位点,设计成一个HCV多表位抗原基因PCX,在大肠杆菌中表达,用此蛋白免疫恒河猴,诱导猴体产生了较高的抗体水平,滴度达11000以上,在免疫后的60周抗体滴度仍达140以上.同时,在免疫后6周用人HCV阳性血清攻击猴子,免疫PCX的猴子出现一过性ALT升高,在攻击后三周内用RT-PCR检测到猴血清内HCV的RNA阳性.结果表明,免疫多表位的PCX蛋白可以诱导机体产生高水平的免疫应答.     

丙型肝炎病毒多表位抗原在恒河猴中的免疫应答及保护性试验

利用ＨＣＶ抗原多表位来研制ＨＣＶ疫苗是目前的一个新方向。本研　究利用ＨＣＶ的ＨＣＶ的５个保守表位串联,并加入破伤风类毒素上的一个Ｔ细胞激活位点,设计成　一个ＨＣＶ多表位抗原基因ＰＣＸ,在大肠杆菌中表达,用此蛋白免疫恒河猴,诱导猴体产生了较　高的抗体水平,滴度达１∶１０００以上,在免疫后的６０周抗体滴度仍达１∶４０以上。同时,在免　疫后６周用人ＨＣＶ阳性血清攻击猴子,免疫ＰＣＸ的猴子出现一过性ＡＬＴ升高,在攻击后三周内用　ＲＴ－ＰＣＲ检测到猴血清内ＨＣＶ的ＲＮＡ阳性。结果表明,免疫多表位的ＰＣＸ蛋白可以诱导机体产生　高水平的免疫应答。