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961.
Michael P. Challen Timothy J. Elliott Ursula Kües Lorna A. Casselton 《Molecular genetics and genomics : MGG》1993,241(3-4):474-478
The A mating factor of Coprinus cinereus determines compatibility in mating by regulating part of a developmental sequence that leads to dikaryon formation. The A genes that trigger development encode two different classes of homeodomain proteins, and for a successful mating, a protein of one class, HD 1, must interact with a protein of the other class, HD 2. In this report we show that C. cinereus A genes that encode HD 2 proteins, a2-1 and b2-1, can elicit A-regulated development in the heterologous host C. bilanatus. Transformation rates were very low, suggesting that the genes were poorly transcribed. The fact that the HD 2 genes are functionally expressed implies successful heteromultimeric association of putative DNA-binding proteins coded by the two Coprinus species. This interaction was sufficient to satisfy the need for different A factors in the formation of a fertile C. bilanatus dikaryon, but fertile dikaryons were more readily produced in matings with the a2-1 gene transformants. The C. cinereus A genes, b1-1 and d1-1, which encode HD1 proteins, were either not expressed or their proteins were non-functional in C. bilanatus. These experiments raise some interesting questions regarding HD1–HD2 protein interactions. 相似文献
962.
Niraj Shrestha Pallavi Chaturvedi Xiaoyun Zhu Michael J. Dee Varghese George Christopher Janney Jack O. Egan Bai Liu Mark Foster Lynne Marsala Pamela Wong Celia C. Cubitt Jennifer A. Foltz Jennifer Tran Timothy Schappe Karin Hsiao Gilles M. Leclerc Lijing You Christian Echeverri Catherine Spanoudis Ana Carvalho Leah Kanakaraj Crystal Gilkes Nicole Encalada Lin Kong Meng Wang Byron Fang Zheng Wang Jin-an Jiao Gabriela J. Muniz Emily K. Jeng Nicole Valdivieso Liying Li Richard Deth Melissa M. Berrien-Elliott Todd A. Fehniger Peter R. Rhode Hing C. Wong 《Aging cell》2023,22(5):e13806
963.
Eleonore Jonas Alexander Dwenger Michael Jonas Michael Nerlich Harald Tscherne 《Luminescence》1993,8(5):253-260
We investigated the effect of prostaglandin E1 on human polymorphonuclear leukocytes, in vivo. Polymorphonuclear leukocytes of a prostaglandin E1 and placebo study group were harvested and their function, as production of oxygen-derived metabolites and adherence to human cultured endothelial cells, was compared. Additionally, data obtained from polymorphonuclear leukocytes of a prostaglandin E1 and placebo group were compared with data obtained from polymorphonuclear leukocytes from 28 blood donors, who served as a control group. Production of oxygen-derived metabolites by polymorphonuclear leukocytes during contact with endothelial cells was measured by chemiluminescence. Chemiluminescence was significantly (p < 0.01) increased in the placebo group in comparison to the control group decreasing to values of control group after 6 d (post-trauma). Chemiluminescence response was not significantly suppressed in patients treated with prostaglandin E1 in comparison to the placebo group. Adherence of polymorphonuclear leukocytes (placebo group) to endothelial cells was significantly increased (p < 0.01) within the first 6 d post-trauma Following day 6, values were in the same range as values for the control group. Adherence was not significantly suppressed in patients treated with prostaglandin E1 in comparison to the placebo group. In conclusion, prostaglandin E1 at a dose of 20 ng/kg bw/min does not influence production of oxygenderived metabolites and adherence in polytraumatized patients in comparison to a placebo group. Additionally, production of oxygen-derived metabolites by polymorphonuclear leukocytes in response to endothelial cells is shown and it is evident that endothelial cells might influence production of oxygen derived metabolites by polymorphonuclear leukocytes. 相似文献
964.
965.
Jeffery B. Press James J. McNally Pauline J. Sanfilippo Michael F. Addo Deborah Loughney Edward Giardino Laurence B. Katz Robert Falotico Barbara J. Haertlein 《Bioorganic & medicinal chemistry》1993,1(6):423-435
The syntheses and antihypertensive activity of the thieno[3,4-b]pyran and thieno[2,3-b]pyran isosteres of the potassium channel opener (PCO) RWJ 26629 (± 2a) are reported. While the unsubstituted thiophene derivatives were active at 20 mg/kg, introduction of a strong electron withdrawing group in the 2-position of the thieno[3,2-b] series increased potency. Similar substitution on the thieno[3,4-b] series significantly lowered potency. Compounds 26 and 30 are approximately 5-fold more potent than the prototypic PCO cromakalim (± 1). 相似文献
966.
The translocation of secretory proteins derived from a Gram-positive (Staphylococcus hyicus prolipase) or a Gram-negative (Escherichia coli pre-OmpA protein) bacterium across the cytoplasmic membrane was studied in E. coli and Bacillus subtilis. in both microorganisms, the prolipase was found to be secreted across the plasma membrane when either the pre-prolipase signal peptide (38 amino acids in length) or the pre-OmpA signal peptide (21 amino acids in length) was used. Expression of the gene encoding the authentic pre-OmpA protein in B. subtilis resulted in the translocation of mature OmpA protein across the plasma membrane. Processing of the OmpA precursor in B. subtilis required the electrochemical potential and was sensitive to sodium azide, suggesting that the B. subtilis SecA homologue was involved in the translocation process. The mature OmpA protein, which was most likely present in an aggregated state, was fully accessible to proteases in protoplasted cells. Therefore, our results clearly demonstrate that an outer membrane protein can be secreted by B. subtilis, supporting the notion that the basic mechanism of protein translocation is highly conserved in Gram-positive and Gram-negative bacteria. 相似文献
967.
968.
Michael A. Poss Joyce A. Reid Charles A. Free W. Lynn Rogers Helen Weber Denis E. Ryono Tamara Dejneka Jack M. DeForrest Thomas L. Waldron Russell J. Brittain Harold N. Weller Maria P. Cimarusti Edward W. Petrillo 《Bioorganic & medicinal chemistry letters》1993,3(12):2739-2744
The syntheses and pharmacological activity of a series of diol sulfonamides which function as inhibitors of human renin are described. The most potent compound in this series, compound 20 (SQ 33,800), is a subnanomolar inhibitor of human renin (IC50 = 0.35 × 10−9 M). 相似文献
969.
Bruce E. Maryanoff Michael J. Costanzo Ricahrd P. Shank James J. Schupsky Marta E. Ortegon Jeffry L. Vaught 《Bioorganic & medicinal chemistry letters》1993,3(12):2653-2656
Exploration structure-activity relationships surrounding the clinically effective antiepileptic drug topiramate (1) led to a series of potent anticonvulsants with a 4,5-cyclic sulfate or 4,5-cycli sulfite functionality. Key derivative 2 (RWJ-37947) is ca. 8 times more potent than topiramate in mice; it also features a long duration of action and a very favorable neurotoxicity index. 相似文献
970.
Christina Seisenberger Tobias Graf Sarah Sticht Markus Haindl Ulrich Mohn Harald Wegele Michael Wiedmann Stefanie Wohlrab 《Biotechnology and bioengineering》2023,120(1):184-193
Host cell proteins (HCPs) are inevitable process-related impurities in biotherapeutics commonly monitored by enzyme-linked immunosorbent assays (ELISAs). Of particular importance for their reliable detection are the anti-HCP polyclonal antibodies (pAbs), supposed to detect a broad range of HCPs. The present study focuses on the identification of suitable host animal species for the development of high-performance CHO-HCP ELISAs, assuming the generation of pAbs with adequate coverage and specificity. Hence, antibodies derived from immunization of sheep, goats, donkeys, rabbits, and chickens were compared concerning their amount of HCP-specific antibodies, coverage, and performance in a sandwich ELISA. Immunization of sheep, goats, donkeys, and rabbits met all test criteria, whereas the antibodies from chickens cannot be recommended based on the results of this study. Additionally, a mixture of antibodies from the five host species was prepared to assess if coverage and ELISA performance can be improved by a multispecies approach. Comparable results were obtained for the single- and multispecies ELISAs in different in-process samples, indicating no substantial improvement for the latter in ELISA performance while raising ethical and financial concerns. 相似文献