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991.
What are the key building blocks that would have been needed to construct complex protein folds? This is an important issue for understanding protein folding mechanism and guiding de novo protein design. Twenty naturally occurring amino acids and eight secondary structures consist of a 28‐letter alphabet to determine folding kinetics and mechanism. Here we predict folding kinetic rates of proteins from many reduced alphabets. We find that a reduced alphabet of 10 letters achieves good correlation with folding rates, close to the one achieved by full 28‐letter alphabet. Many other reduced alphabets are not significantly correlated to folding rates. The finding suggests that not all amino acids and secondary structures are equally important for protein folding. The foldable sequence of a protein could be designed using at least 10 folding units, which can either promote or inhibit protein folding. Reducing alphabet cardinality without losing key folding kinetic information opens the door to potentially faster machine learning and data mining applications in protein structure prediction, sequence alignment and protein design. Proteins 2015; 83:631–639. © 2015 Wiley Periodicals, Inc. 相似文献
992.
A high‐performance liquid chromatography (HPLC) method was established to detect Xeljanz enantiomers in active pharmaceutical ingredients (APIs) and tablets. The separation was achieved on a Chiralpak IC column using a mobile phase of hexane‐ethanol‐diethylamine (65:35:0.1, v/v). The detection wavelength was 289 nm. The peak areas and the enantiomer concentrations in the range of 0.15–2.25 μg?mL?1 were in high linearity, with correlation coefficients higher than 0.999. The recoveries were 86.44% at the concentrations of 7.5, 18.75, and 37.5 μg?mL?1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.042 and 0.14 μg?mL?1, respectively. This HPLC method is suitable for detecting the enantiomers of Xeljanz in its APIs and tablets. Chirality 27:235–238, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
993.
The Crc protein participates in down‐regulation of the Lon gene to promote rhamnolipid production and rhl quorum sensing in Pseudomonas aeruginosa 下载免费PDF全文
994.
Eliana F. Oliveira Marcelo Gehara Vinícius A. São‐Pedro Xin Chen Edward A. Myers Frank T. Burbrink Daniel O. Mesquita Adrian A. Garda Guarino R. Colli Miguel T. Rodrigues Federico J. Arias Hussam Zaher Rodrigo M. L. Santos Gabriel C. Costa 《Molecular ecology》2015,24(23):5957-5975
Two main hypotheses have been proposed to explain the diversification of the Caatinga biota. The riverine barrier hypothesis (RBH) claims that the São Francisco River (SFR) is a major biogeographic barrier to gene flow. The Pleistocene climatic fluctuation hypothesis (PCH) states that gene flow, geographic genetic structure and demographic signatures on endemic Caatinga taxa were influenced by Quaternary climate fluctuation cycles. Herein, we analyse genetic diversity and structure, phylogeographic history, and diversification of a widespread Caatinga lizard (Cnemidophorus ocellifer) based on large geographical sampling for multiple loci to test the predictions derived from the RBH and PCH. We inferred two well‐delimited lineages (Northeast and Southwest) that have diverged along the Cerrado–Caatinga border during the Mid‐Late Miocene (6–14 Ma) despite the presence of gene flow. We reject both major hypotheses proposed to explain diversification in the Caatinga. Surprisingly, our results revealed a striking complex diversification pattern where the Northeast lineage originated as a founder effect from a few individuals located along the edge of the Southwest lineage that eventually expanded throughout the Caatinga. The Southwest lineage is more diverse, older and associated with the Cerrado–Caatinga boundaries. Finally, we suggest that C. ocellifer from the Caatinga is composed of two distinct species. Our data support speciation in the presence of gene flow and highlight the role of environmental gradients in the diversification process. 相似文献
995.
996.
GmWRKY27 interacts with GmMYB174 to reduce expression of GmNAC29 for stress tolerance in soybean plants 总被引:1,自引:0,他引:1 下载免费PDF全文
997.
Longbiao Guo Jie Qiu Zujing Han Zihong Ye Chao Chen Chuanjun Liu Xiufang Xin Chu‐Yu Ye Ying‐Ying Wang Hongqing Xie Yu Wang Jiandong Bao She Tang Jie Xu Yijie Gui Fei Fu Weidi Wang Xingchen Zhang Qianhua Zhu Xuanmin Guang Chongzhi Wang Haifeng Cui Daguang Cai Song Ge Gerald A. Tuskan Xiaohan Yang Qian Qian Sheng Yang He Jun Wang Xue‐Ping Zhou Longjiang Fan 《The Plant journal : for cell and molecular biology》2015,83(4):600-609
998.
Zheng Li Xin Yu Jianxiong Shen Yang Liu Matthew T. V. Chan William K. K. Wu 《Cell proliferation》2015,48(5):511-516
Rhabdomyosarcoma (RMS) is the most common of the soft tissue sarcomas with resultant high morbidity, frequently occuring in paediatric patients and young adults. While the molecular basis of RMS has received considerable attention, exact mechanisms underlying its development and metastasis remain unclear. MicroRNAs (miRNAs) are endogenously expressed small non‐coding RNAs that negatively regulate gene expression via translational inhibition or mRNA degradation. Deregulated expression of miRNA has been implicated in initiation, progression, and metastasis of RMS. miRNAs have emerged as key regulators of several physiological and pathophysiological processes and have opened new avenues for diagnosis and treatment of RMS. This review summarizes deregulation and functional roles of miRNAs in RMS and their potential applications for diagnosis, prognosis and treatment of this malignancy. As a rapidly evolving field in basic and translational medicine, it is hopeful that miRNA research will ultimately improve management of RMS. 相似文献
999.
1000.