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961.
Xunlong Shi Zhihui Shi Hai Huang Hongguang Zhu Haiyan Zhu Dianwen Ju Pei Zhou 《Applied microbiology and biotechnology》2013,97(23):10025-10033
Therapeutic recombinant human catalase (rhCAT) can quench infection-induced reactive oxygen species (ROS), thereby alleviating the associated tissue damage. Although the intranasal route is efficient to deliver native rhCAT to the lung, the therapeutic effect is limited by rapid elimination from the blood. In this study, we modified rhCAT with the active polymer, polyethylene glycol monomethyl ether (PEG)-5000, and analyzed the pharmacokinetics of PEGylated rhCAT in mice. The high tetra-PEGylation ratio was about 60 %, and PEGylation prolonged the half-life of rhCAT in serum (75 vs. 13.5 min for native rhCAT). The protective effects of PEG-rhCAT were investigated in a mouse model of influenza virus A (H1N1)-associated pneumonia. PEG-rhCAT was more effectively delivered than native rhCAT and was associated with higher survival ratio, less extensive lung injuries, reduced ROS levels, and lower viral replication. Collectively, these findings indicate that PEGylation can enhance the therapeutic efficacy of native rhCAT and suggest that PEGylated rhCAT may represent a novel complement therapy for H1N1 influenza-induced pneumonia. 相似文献
962.
Yu-Cai He Cui-Luan Ma Zhen-Xing Yang Min Zhou Zhen Xing Jiang-Tao Ma Hui-Lei Yu 《Applied microbiology and biotechnology》2013,97(24):10329-10337
Enantiopure sulfoxides can be prepared via the asymmetric oxidation of sulfides using sulfide monooxygenases. The n-octane–water biphasic system was chosen for the bio-oxidation of a water-insoluble phenyl methyl sulfide (PMS) by Rhodococcus sp. CCZU10-1. In this n-octane–water system, the optimum reaction conditions were obtained. (S)-phenyl methyl sulfoxide ((S)-PMSO) with >99.9 % enantiomeric excess formed at 55.3 mM in the n-octane–water biphasic system. Using fed-batch method, a total of 118 mM (S)-PMSO accumulated in 1-L reaction mixture after the 7th feed, and no (R)-PMSO and sulfone were detected. Moreover, Rhodococcus sp. CCZU10-1 displayed fairly good activity and enantioselectivity toward other sulfides. In conclusion, Rhodococcus sp. CCZU10-1 is a promising biocatalyst for synthesizing highly optically active sulfoxides. 相似文献
963.
In vitro rapid evolution of fungal immunomodulatory proteins by DNA family shuffling 总被引:1,自引:0,他引:1
Xue-Fei Wang Qi-Zhang Li Ting-Wen Bao Wei-Ran Cong Wen-Xia Song Xuan-Wei Zhou 《Applied microbiology and biotechnology》2013,97(6):2455-2465
Fungal immunomodulatory proteins (FIPs) found in a wide variety of mushrooms hold significant therapeutic potential. Despite much research, the structural determinants for their immunomodulatory functions remain unknown. In this study, a DNA shuffling technique was used to create two shuffled FIP protein libraries: an intrageneric group containing products of shuffling between FIP-glu (FIP gene isolated from Ganoderma lucidum) and FIP-gsi (FIP gene isolated from Ganoderma sinense) genes and an intergeneric group containing the products of shuffling between FIP-glu, FIP-fve (FIP gene isolated from Flammulina velutipes), and FIP-vvo (FIP gene isolated from Volvariella volvacea) genes. The gene shuffling generated 426 and 412 recombinant clones, respectively. Using colony blot analysis, we selected clones that expressed relatively high levels of shuffled gene products recognized by specific polyclonal antibodies. We analyzed the DNA sequences of the selected shuffled genes, and testing of their protein products revealed that they maintained functional abilities to agglutinate blood cells and induce cytokine production by splenocytes from Kunming mice in vitro. Meanwhile, the relationships between protein structure and the hemagglutination activity and between the changed nucleotide sites and expression levels were explored by bioinformatic analysis. These combined analyses identified the nucleotide changes involved in regulating the expression levels and hemagglutination activities of the FIPs. Therefore, we were able to generate recombinant FIPs with improved biological activities and expression levels by using DNA shuffling, a powerful tool for the generation of novel therapeutic proteins and for their structural and functional studies. 相似文献
964.
Zhonghua Liu Yijun Dai Yu Huan Zhenxing Liu Lei Sun Qianwen Zhou Wenjian Zhang Qi Sang Hua Wei Sheng Yuan 《Applied microbiology and biotechnology》2013,97(14):6537-6547
Imidacloprid, the largest selling insecticide in the world, is more stable in soil, and its environmental residue and effects are attracting people's close attention. One of imidacloprid metabolism pathways was degraded to CO2 through olefin imidacloprid pathway. Here, we report that sucrose as a utilizable substrate enhanced the cometabolism of imidacloprid by Stenotrophomonas maltophilia CGMCC 1.1788 to produce 5-hydroxy imidacloprid, whereas when succinate was used as a utilizable substrate, 5-hydroxy imidacloprid from imidacloprid was transformed to olefin imidacloprid, and the latter was further degraded. The hydroxylation of imidacloprid required NAD(P)H, whereas the dehydration of 5-hydroxy imidacloprid to form olefin imidacloprid required succinate rather than NAD(P)H. NADPH greatly favored the hydroxylation of imidacloprid more than NADH, and NADPH inhibited the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid, but NADH did not. Therefore, sucrose may be metabolized through hexose monophosphate pathway to produce mainly NADPH which participated in the hydroxylation of imidacloprid to 5-hydroxy imidacloprid and meanwhile inhibited the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid, whereas succinate may be metabolized mainly through the tricarboxylic acid cycle to produce NADH which was involved in hydroxylation of imidacloprid to 5-hydroxy imidacloprid but did not inhibit the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid. Our results have a significant meaning in further understanding the influence of different utilizable substrates on the cometabolic pathways and the fate of environmental imidacloprid. 相似文献
965.
Xilin Du Yaqian Li Wanping Zhou Quan Zhou Haiming Liu Yuquan Xu 《Applied microbiology and biotechnology》2013,97(17):7767-7778
We constructed a non-scar triple-deleted mutant Pseudomonas aeruginosa to improve phenazine-1-carboxylic acid (PCA) yield and then optimized the culture conditions for PCA production. Using a non-scar deletion strategy, the 5′-untranslated region of the phz1 gene cluster and two genes, phzM and phzS, were knocked out of the P. aeruginosa strain M18 genome. The potential ability for high-yield PCA production in this triple-deleted mutant M18MSU1 was successfully realized by using statistical experimental designs. A 25–1 fractional factorial design was used to show that the three culture components of soybean meal, corn steep liquor and ethanol had the most significant effect on PCA production. Using a central composite design, the concentration of the three components was optimized. The maximum PCA production was predicted to be 4,725.1 mg/L. With the optimal medium containing soybean meal 74.25 g/L, corn steep liquor 13.01 g/L and ethanol 21.84 ml/L, a PCA production of 4,771.2 mg/L was obtained in the validation experiments, which was nearly twofold of that before optimization and tenfold of that in the wild-type strain. This non-scar triple-deleted mutant M18MSU1 may be a suitable strain for industrial production of this biologically synthesized fungicide due to its high PCA production, presumed safety, thermal adaptability and cost-effectiveness. 相似文献
966.
Megan A. Owen Ronald R. Swaisgood Laura McGeehan Xiaoping Zhou Donald G. Lindburg 《Ethology : formerly Zeitschrift fur Tierpsychologie》2013,119(10):869-880
Giant panda courtship behavior includes multimodal signaling assemblages consisting of olfactory, vocal, and postural elements. While signaling is generally conspicuous, successful copulation is inconsistently achieved in captivity, even when female behavioral and physiological data indicate that ovulation is imminent. We set out to characterize these complex patterns of social behavior by observing interactions between 26 unique pairs of giant pandas housed in adjoining pens throughout the females' reproductive cycle. We categorized social behaviors from a transactional perspective and examined social exchanges via analyses of the relative frequency of social behaviors, and via the sequential relationship between male and female social behavior. From non‐estrus to peak‐estrus, we found that the relative frequency of female affiliative and sexual behavior increased and that the relative frequency of ambivalent and aggressive behavior decreased. Male behavior was fairly constant, except for sexual behavior, which increased during peak‐estrus, when it was facilitated by female sexual behavior. Sequential analysis of social interactions showed that preceding behavior had a significant influence over the other panda's response behavior primarily during peak‐estrus, suggesting that pandas are most responsive to conspecific signaling during the peri‐ovulatory period. However, behavioral momentum was a dominant feature of the intra‐individual transitions. Females maintained sexual, ambivalent, and neutral behavior during interactions significantly more than would be expected by chance, with male behavior bearing little influence once the behavior was initiated. A similar pattern was also observed in males, who maintained affiliative, interested, and neutral behaviors. Overall, our data suggest that the multimodal signals used by giant pandas during courtship do not consistently evoke a discrete, immediate response from receivers. Instead, signals appear to advertise reproductive condition and influence potential mates over longer timeframes, suggesting the potential tonic role of communication. 相似文献
967.
Yanli Zhang Lina Wang Wenhao Zhou Huijun Wang Jin Zhang Shanshan Deng Weihua Li Huawei Li Zuohua Mao Duan Ma 《Developmental biology》2013
Tissue factor pathway inhibitor-2 (Tfpi-2) is an important serine protease inhibitor in the extracellular matrix (ECM), but its precise physiological significance remains unknown. This work is part of a series of studies intended to investigate functional roles of Tfpi-2 and explore the underlying molecular mechanisms. First, we cloned and identified zebrafish Tfpi-2 (zTfpi-2) as an evolutionarily conserved protein essential for zebrafish development. We also demonstrated that ztfpi-2 is mainly expressed in the central nervous system (CNS) of zebrafish, and embryonic depletion of ztfpi-2 caused severe CNS defects. In addition, changes of neural markers, including pax2a, egr2b, huC, ngn1, gfap and olig2, confirmed the presence of developmental abnormalities in the relevant regions of ztfpi-2 morphants. Using microarray analysis, we found that members of the Notch pathway, especially her4 and mib, which mediate lateral inhibition in CNS development, were also downregulated. Intriguingly, both her4 and mib were able to partially rescue the ztfpi-2 morphant phenotype. Furthermore, Morpholino knockdown of ztfpi-2 resulted in upregulation of neuronal markers while downregulation of glial markers, providing evidence that the Notch pathway is probably involved in ztfpi-2-mediated CNS development. 相似文献
968.
Lifeng Yan Yong Zhou Shanhe Yu Guixiang Ji Lei Wang Wei Liu Aihua Gu 《Experimental cell research》2013
Genomic damage may devastate the potential of progenitor cells and consequently impair early organogenesis. We found that ogg1, a key enzyme initiating the base-excision repair, was enriched in the embryonic heart in zebrafish. So far, little is known about DNA repair in cardiogenesis. Here, we addressed the critical role of ogg1 in cardiogenesis for the first time. ogg1 mainly expressed in the anterior lateral plate mesoderm (ALPM), the primary heart tube, and subsequently the embryonic myocardium by in situ hybridisation. Loss of ogg1 resulted in severe cardiac morphogenesis and functional abnormalities, including the short heart length, arrhythmia, decreased cardiomyocytes and nkx2.5+ cardiac progenitor cells. Moreover, the increased apoptosis and repressed proliferation of progenitor cells caused by ogg1 deficiency might contribute to the heart phenotype. The microarray analysis showed that the expression of genes involved in embryonic heart tube morphogenesis and heart structure were significantly changed due to the lack of ogg1. Among those, foxh1 is an important partner of ogg1 in the cardiac development in response to DNA damage. Our work demonstrates the requirement of ogg1 in cardiac progenitors and heart development in zebrafish. These findings may be helpful for understanding the aetiology of congenital cardiac deficits. 相似文献
969.
Ahmed Abdelmoniem Mousa Shinuo Cao Gabriel Oluga Aboge Mohamad Alaa Terkawi Ahmed El Kirdasy Akram Salama Mabrouk Attia Mahmoud Aboulaila Mo Zhou Ketsarin Kamyingkird Paul Franck Adjou Moumouni Tatsunori Masatani Sami Ahmed Abd El Aziz Waheed Mohammed Moussa Bayin Chahan Shinya Fukumoto Yoshifumi Nishikawa Salah Sayed El Ballal Xuenan Xuan 《Experimental parasitology》2013
Identification and molecular characterization of Babesia gibsoni proteins with potential antigenic properties are crucial for the development and validation of the serodiagnostic method. In this study, we isolated a cDNA clone encoding a novel B. gibsoni 76-kDa protein by immunoscreening of the parasite cDNA library. Computer analysis revealed that the protein presents a glutamic acid-rich region in the C-terminal. Therefore, the protein was designated as B. gibsoni glutamic acid-rich protein (BgGARP). A BLASTp analysis of a translated BgGARP polypeptide demonstrated that the peptide shared a significant homology with a 200-kDa protein of Babesia bigemina and Babesia bovis. A truncated BgGARP cDNA (BgGARPt) encoding a predicted 13-kDa peptide was expressed in Escherichia coli (E. coli), and mouse antisera against the recombinant protein were used to characterize a corresponding native protein. The antiserum against recombinant BgGARPt (rBgGARPt) recognized a 140-kDa protein in the lysate of infected erythrocytes, which was detectable in the cytoplasm of the parasites by confocal microscopic observation. In addition, the specificity and sensitivity of enzyme-linked immunosorbent assay (ELISA) with rBgGARPt were evaluated using B. gibsoni-infected dog sera and specific pathogen-free (SPF) dog sera. Moreover, 107 serum samples from dogs clinically diagnosed with babesiosis were examined using ELISA with rBgGARPt. The results showed that 86 (80.4%) samples were positive by rBgGARPt-ELISA, which was comparable to IFAT and PCR as reference test. Taken together, these results demonstrate that BgGARP is a suitable serodiagnostic antigen for detecting antibodies against B. gibsoni in dogs. 相似文献
970.
Probabilities of disorder for FlgM proteins of 39 species whose optimal growth temperature ranges from 273 K (0°C) to 368 K (95°C) were predicted by a newly developed method called Sequence-based Prediction with Integrated NEural networks for Disorder (SPINE-D). We showed that the temperature-dependent behavior of FlgM proteins could be separated into two subgroups according to their sequence lengths. Only shorter sequences evolved to adapt to high temperatures (>318 K or 45°C). Their ability to adapt to high temperatures was achieved through a transition from a fully disordered state with little secondary structure to a semidisordered state with high predicted helical probability at the N-terminal region. The predicted results are consistent with available experimental data. An analysis of all orthologous protein families in 39 species suggests that such a transition from a fully disordered state to semidisordered and/or ordered states is one of the strategies employed by nature for adaptation to high temperatures. 相似文献