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91.
百合查尔酮合成酶(CHS)基因的克隆与分析 总被引:3,自引:0,他引:3
以东方百合“索邦”基因组DNA为模板进行PCR扩增,将得到的目的片段克隆至pGEM-T easy载体后进行测序.结果表明,目的序列全长1 307 bp,经BLA ST分析,与鸢尾、玉米、水稻等植物的查尔酮合成酶(CHS)基因核苷酸同源性在70%以上;与已经克隆的CHS cDNA序列相比,CHS DNA序列中包含2个外显子和1个内含子,内含子全长82 bp,符合TG-AG特征.将得到的序列提交G enB ank,序列号为DQ 471951. 相似文献
92.
一种基于单分子纳米操纵的有序化测序策略 总被引:1,自引:0,他引:1
尽管包括人类在内的许多生物物种的基因组测序工作已经完成,但由于现有测序技术的限制,大部分复杂基因组还存在很多大大小小的缺口.缺口的填补以及对其他重复序列区域的测序迫切需要全新的思路和技术.基于在DNA单分子定位切割和拾取方面的实验进展,提出了一种基于原子力显微镜纳米操纵技术的单分子有序化测序策略.计算机模拟的结果表明,这一方法和策略是可行的,有助于解决目前测序工作中所遇到的一些棘手问题. 相似文献
93.
94.
Use of DNA markers to study bird migration 总被引:2,自引:2,他引:0
Michael Wink 《Journal of Ornithology》2006,147(2):234-244
The molecular methods that are presently being used for studying phylogenetics, phylogeography and population genetics can
also be applied to study bird migration. They are powerful and can supplement the information obtained from ringing, telemetry,
morphometrics, ringing, radar tracking and isotope analysis. This short review describes the principles, scopes and limitations
DNA methods and DNA markers that are relevant for migration research, such as DNA sequences, short tandem repeats (microsatellites),
single nucleotide polymorphisms, amplified fragment length polymorphism, inter simple sequence repeats and molecular sexing. 相似文献
95.
对厚荚相思(Acaciacrassicarpa)根瘤菌HJ06菌株的16SrDNA全序列和nifA基因片段进行了测定。结果表明,HJ06菌株在以16SrDNA序列构建的系统发育树状图中位于根瘤菌属(Rhizobium)分支中,与根瘤菌属各个种的相似性达95%以上;从HJ06菌株克隆出的585bpnifA基因片段与Klebsiellapneumoniae的同源性达到99.3%,与Klebsiellaoxytoca的NifF,NifL,NifA,NifB蛋白基因的同源性为97.8%。 相似文献
96.
Corina Krause Jochen Kirschbaum Günther Jung Hans Brückner 《Journal of peptide science》2006,12(5):321-327
From the culture broth of the mold Trichoderma viride, strain 63 C-I, the polypeptide antibiotic suzukacillin (SZ) was isolated. A peptide mixture named SZ-A was obtained by crystallization from crude SZ. Individual peptides from SZ-A were isolated by semipreparative HPLC and sequences were determined by HPLC-ESI-MS. The data confirm a general sequence of SZ-A published previously and in addition establish the individual sequences of 15 acetylated eicosa peptides with C-terminal alcohols. The major peptide SZ-A4 (21% of all peptides) shows the sequence:Ac-Aib-Ala-Aib-Ala-Aib-Ala(6)-Gln-Aib-Lx(9)-Aib-Gly-Aib(12)-Aib-Pro-Vx(15)-Aib-Vx(17)-Gln-Gln-Fol. Amino acid exchanges of the peptaibol are located in position 6 (Ala/Aib), 9 (Vx/Lx), 12 (Aib/Lx), 17 (Aib/Vx) and possibly at position15 (Val/Iva) (uncommon abbreviations: Aib (alpha-aminoisobutyric acid); Iva (D-isovaline); Lx (L-leucine or L-isoleucine); Vx (L-valine or D-isovaline); Fol (L-phenylalaninol)). 相似文献
97.
DNA条形码是利用标准的DNA片段对物种进行快速鉴定的技术,已在生物学各相关领域得到广泛应用。随着DNA条形码技术的不断发展和完善,已成功应用于生态学领域的相关研究中。本文综述了DNA条形码在物种快速鉴定和隐存种发现、群落系统发育重建和生态取证、群落内物种间相互关系研究等方面的应用,并介绍了DNAmetabarcoding技术和环境DNA条形码在生物多样性和生态学研究领域中的应用。最后,结合新的测序技术和未来大科学装置的发展,在相关数据库逐渐完善,新分析方法和计算模型不断开发使用的情景下,对DNA条形码在生态学相关领域的应用前景进行了展望。 相似文献
98.
Animal models provide myriad benefits to both experimental and clinical research. Unfortunately, in many situations, they fall short of expected results or provide contradictory results. In part, this can be the result of traditional molecular biological approaches that are relatively inefficient in elucidating underlying molecular mechanism. To improve the efficacy of animal models, a technological breakthrough is required. The growing availability and application of the high-throughput methods make systematic comparisons between human and animal models easier to perform. In the present study, we introduce the concept of the comparative systems biology, which we define as "comparisons of biological systems in different states or species used to achieve an integrated understanding of life forms with all their characteristic complexity of interactions at multiple levels". Furthermore, we discuss the applications of RNA-seq and ChIP-seq technologies to comparative systems biology between human and animal models and assess the potential applications for this approach in the future studies. 相似文献
99.
AbstractKrishna Godavari (KG) basin, located in the eastern continental margin of India, is a geological region well known for the abundance of economically important minerals. However, less is known about the microbial ecology of its subsurface sediments. The present study is the first report on the comprehensive culture-independent census of bacterial communities of deep subsurface of KG basin and their relationship with the geochemical environment. Elemental and mineralogical characterization of the sediments highlighted the presence of carbon and nitrogen deprived conditions along with the abundance of metalliferous minerals, especially rich in valuable elements like zirconium, vanadium, cesium, and rare earth elements. Diversity analysis based on Illumina MiSeq high-throughput sequencing platform revealed the predominance of Firmicutes (44.24%), Proteobacteria (34.17%), Bacteroidetes (15.18%), and Actinobacteria (3.81%) in the deep subsurface of this basin. ‘Abundant’ and ‘rare’ sub-communities analysis indicated that a large number of phyla like Acidobacteria, Armatimonadetes, Chloroflexi, and Deinococcus-Thermus were exclusively present as a rare community. Statistical analyses demonstrated that geochemical parameters, especially depth, pH, and metal content, showed significant influence on the microbial community structure. The present study should help future investigations for microbial mediated sustainable utilization of mineral-rich sediments of the region. 相似文献
100.
Olga De Castro Antonietta Di Maio José Armando Lozada García Danilo Piacenti Mario Vázquez-Torres Paolo De Luca 《Annals of botany》2013,112(3):589-602