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Ji Guo Su Xiao Ming Han Xiao Zhang Yan Xue Hou Jian Zhuo Zhu Yi Dong Wu 《Journal of biomolecular structure & dynamics》2016,34(3):560-571
Protein collective motions play a critical role in many biochemical processes. How to predict the functional motions and the related key residue interactions in proteins is important for our understanding in the mechanism of the biochemical processes. Normal mode analysis (NMA) of the elastic network model (ENM) is one of the effective approaches to investigate the structure-encoded motions in proteins. However, the motion modes revealed by the conventional NMA approach do not necessarily correspond to a specific function of protein. In the present work, a new analysis method was proposed to identify the motion modes responsible for a specific function of proteins and then predict the key residue interactions involved in the functional motions by using a perturbation approach. In our method, an internal coordinate that accounts for the specific function was introduced, and the Cartesian coordinate space was transformed into the internal/Cartesian space by using linear approximation, where the introduced internal coordinate serves as one of the axes of the coordinate space. NMA of ENM in this internal/Cartesian space was performed and the function-relevant motion modes were identified according to their contributions to the specific function of proteins. Then the key residue interactions important for the functional motions of the protein were predicted as the interactions whose perturbation largely influences the fluctuation along the internal coordinate. Using our proposed methods, the maltose transporter (MalFGK2) from E. Coli was studied. The functional motions and the key residue interactions that are related to the channel-gating function of this protein were successfully identified. 相似文献
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Chungwen Wei Eugene Storozynsky A. J. McAdam Kun-Yun Yeh Brian R. Tilton Richard A. Willis Richard K. Barth R. John Looney Edith M. Lord J. G. Frelinger 《Cancer immunology, immunotherapy : CII》1996,42(6):362-368
Human prostate-specific antigen (PSA) has a highly restricted tissue distribution. Its expression is essentially limited
to the epithelial cells of the prostate gland. Moreover, it continues to be synthesized by prostate carcinoma cells. This
makes PSA an attractive candidate for use as a target antigen in the immunotherapy of prostate cancer. As a first step in
characterizing the specific immune response to PSA and its potential use as a tumor-rejection antigen, we have incorporated
PSA into a well-established mouse tumor model. Line 1, a mouse lung carcinoma, and P815, a mouse mastocytoma, have been transfected
with the cDNA for human PSA. Immunization with a PSA-expressing tumor cell line demonstrated a memory response to PSA which
protected against subsequent challenge with PSA-expressing, but not wild-type, tumors. Tumor-infiltrating lymphocytes could
be isolated from PSA-expressing tumors grown in naive hosts and were specifically cytotoxic against a syngeneic cell line
that expressed PSA. Immunization with tumor cells resulted in the generation of primary and memory cytotoxic T lymphocytes
(CTL) specific for PSA. The isolation of PSA-specific CTL clones from immunized animals further demonstrated that PSA can
serve as a target antigen for antitumor CTL. The immunogenicity studies carried out in this mouse tumor model provide a rationale
for the design of methods to elicit PSA-specific cell-mediated immunity in humans.
Received: 4 April 1996 / Accepted: 31 May 1996 相似文献
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Cun-Feng Zhao Ran Wei Xian-Chun Zhang 《Cladistics : the international journal of the Willi Hennig Society》2020,36(4):443-445
Here, we publish Lepisorus sect. Paragramma (Blume) C.F. Zhao, R. Wei & X.C. Zhang as a combinatio nova to replace the section name in Zhao et al. (2020), which was published as a status nova and turned out to be an invalid name, because we cited an incorrect basionym. A revised infrageneric classification of Lepisorus also is proposed. 相似文献
6.
Wei Lu 《Evolution; international journal of organic evolution》2020,74(8):1879-1880
What determines the rate at which species adapt to new climatic conditions? Weaver et al. found that the evolution of short larval periods promotes climatic niche evolution in salamanders in the genus Desmognathus. 相似文献
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Dongxue Yin Wei Liu Ningning Zhai Yongzhong Feng Gaihe Yang Xiaojiao Wang Xinhui Han 《PloS one》2015,10(5)
This study investigated the effect of sunlight-dark conditions on volatile fatty acids (VFAs), total ammonium nitrogen (TAN), total alkalinity (TA) and pH during pig manure (PM) digestion and then the subsequent influence on biogas yield of PM. PM1 and PM2 were performed in a transparent reactor and a non-transparent reactor, respectively. Two sets of experiments were conducted with a temperature of 35.0±2.0 °C and a total solid concentration of 8.0% to the digestion material. The dynamic change of the four parameters in response to sunlight-dark conditions resulted in variations of the physiological properties in the digester and affected the cumulative biogas production (CBP). PM1 obtained higher CBP (15020.0 mL) with a more stable pH and a lower TAN concentration (1414.5 mg/L) compared to PM2 (2675.0 mL and 1670.0 mg/L, respectively). The direct path coefficients and indirect path coefficients between the four parameters and CBP were also analyzed. 相似文献
10.
Hong Jun Jeon Young Rong Bang Hye Youn Park Seul A. Kim 《Chronobiology international》2017,34(6):677-686
Various physiological and psychological functions are influenced by circadian typology (CT), which was reported to be related to resilience. However, few studies have assessed the effects of CT in relation to resilience. The aim of the present study was to assess the influence of CT on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience. The present study included a total of 1794 healthy hospital employees, and they completed the Morningness–Eveningness Questionnaire, Connor–Davidson Resilience Scale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Hospital Anxiety and Depression Scale and World Health Organization Quality of Life Scale Abbreviated Version. Subjects with evening type showed lower sleep quality, more daytime sleepiness and physical fatigue than neither types and morning types. Additionally, evening types were more depressed and anxious and reported a poorer quality of life. CT was found to be a significant predictor of sleep quality, but CT was minimally associated with physical fatigue and psychological well-being in the regression analysis. Instead, resilience was substantially related to all of the variables measured. In conclusion, CT independently predicts sleep quality, but the effects of CT on physical fatigue and psychological well-being are negligible compared to those of resilience. 相似文献