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141.
William Bateman 《CMAJ》1987,136(4):410-415
142.
Chihiro Sato Nicolas R. Barthélemy Kwasi G. Mawuenyega Bruce W. Patterson Brian A. Gordon Jennifer Jockel-Balsarotti Melissa Sullivan Matthew J. Crisp Tom Kasten Kristopher M. Kirmess Nicholas M. Kanaan Kevin E. Yarasheski Alaina Baker-Nigh Tammie L.S. Benzinger Timothy M. Miller Celeste M. Karch Randall J. Bateman 《Neuron》2018,97(6):1284-1298.e7
143.
M. Fatima Grossi de Sa T. Erik Mirkov Masao Ishimoto Gabriella Colucci Kaye S. Bateman Maarten J. Chrispeels 《Planta》1997,203(3):295-303
Cultivated varieties of the common bean (Phaseolus vulgaris L.) contain an α-amylase inhibitor (αAI-1) that inhibits porcine pancreatic α-amylase (PPA; EC 3.2.1.1) and the amylases
of certain seed weevils, but not that of the Mexican bean weevil, Zabrotes subfasciatus. A variant of αAI-1, called αAI-2, is found in certain arcelin-containing wild accessions of the common bean. The variant
αAI-2 inhibits Z. subfasciatus α-amylase (ZSA), but not PPA. We purified αAI-2 and studied its interaction with ZSA. The formation of the αAI-2-ZSA complex
is time-dependent and occurs maximally at pH 5.0 or below. When a previously isolated cDNA assumed to encode αAI-2 was expressed
in transgenic tobacco seeds, the seeds contained inhibitory activity toward ZSA but not toward PPA, confirming that the cDNA
encodes αAI-2. The inhibitors αAI-1 and αAI-2 share 78% sequence identity at the amino acid level and they differ in an important
region that is part of the site where the enzyme binds the inhibitor. The swap of a tripeptide in this region was not sufficient
to change the specificity of the two inhibitors towards their respective enzymes. The three-dimensional structure of the αAI-1/PPA
complex has just been solved and we recently obtained the derived amino acid sequence of ZSA. This additional information
allows us to discuss the results described here in the framework of the amino acid residues of both proteins involved in the
formation of the enzyme-inhibitor complex and to pinpoint the amino acids responsible for the specificity of the interaction.
Received: 14 April 1997 / Accepted: 10 May 1997 相似文献
144.
N Ruangpanit D Chan K Holmbeck H Birkedal-Hansen J Polarek C Yang J F Bateman E W Thompson 《Matrix biology》2001,20(3):193-203
The respective requirements of collagen and MT1-MMP in the activation of MMP-2 by primary fibroblast cultures were explored further. Three-dimensional gels enriched in human collagen types I and III or composed of recombinant human type II or III collagen, caused increased MT1-MMP production (mRNA and protein) and induced MMP-2 activation. Only marginal induction was seen with dried monomeric collagen confirming the need for collagen fibrillar organisation for activation. To our surprise, relatively low amounts (as low as 25 microg/ml) of acid soluble type I collagen added to fibroblast cultures also induced potent MMP-2 activation. However, the requirement for collagen fibril formation by the added collagen was indicated by the inhibition seen when the collagen was pre-incubated with a fibril-blocking peptide, and the reduced activation seen with alkali-treated collagen preparations known to have impaired fibrilisation. Pre-treatment of the collagen with sodium periodate also abrogated MMP-2 activation induction. Further evidence of the requirement for collagen fibril formation was provided by the lack of activation when type IV collagen, which does not form collagen fibrils, was added in the cultures. Fibroblasts derived from MT1-MMP-deficient mice were unable to activate MMP-2 in response to either three-dimensional collagen gel or added collagen solutions, compared to their littermate controls. Collectively, these data indicate that the fibrillar structure of collagen and MT1-MMP are essential for the MMP-2 activational response in fibroblasts. 相似文献
145.
Angela E. Bateman 《Cell proliferation》1974,7(5):451-461
Inhibitors of DNA synthesis released into balanced salt solution by rat erythrocytes and by rat leucocytes have been found to possess target-cell-specific properties which would be expected of chalones. When assayed in short-term in vitro cultures the erythrocyte product reduced DNA synthesis (as measured autoradiographically) in erythroblasts present in populations of bone-marrow cells but did not affect the DNA synthesis in myeloid or lymphoid cells. The leucocyte product, under the same culture conditions, reduced DNA synthesis in leucocyte precursor cells. The grain counts over nuclei of different cell types were recorded as well as the DNA labelling index. Results so far obtained cannot ascribe the erythrocyte-chalone-produced reduction in labelling index to a blockage of entry into S phase. This cell-specific inhibitor may reduce continuing DNA synthesis in S phase cells to undetectable levels, compared with synthesis in control media. The leucocyte product, however, most probably prevents entry of leucocyte precursor cells into S phase. Possible relevance of these inhibitors as components of physiological control mechanisms or as therapeutic agents is discussed. 相似文献
146.
147.
Francesco D'Amato G. P. Frets O. H. Pearson Richard Hopp G. W Bonn Charles M. Rick Jeanette Robinson Darrell G. Wells G. K. Bondarenko B. I. Chmelev O. Heinisch Earlene Atchison A. J. Bateman K. Mather Werner Gottschalk Donald H. Scott Deane C. Arny K. S. Dodds F. W. Cope Franz Frimmel N. Hess G. Mrkos F. Graf Mengersen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1953,23(6):190-192
Ohne Zusammenfassung 相似文献
148.
Ohne ZusammenfassungWir danken Herrn Prof. K. W. Hau\er, der leider die Ergebnisse der vorliegenden Untersuchungen nicht mehr erleben konnte, für die hilfsbereite Förderung und Unterstützung unserer Arbeit. Die sachliche Untersuchung des Problems lag ihm besonders am Herzen. Zu Dank verpflichtet sind wir ferner Herrn Prof. O. Meyerhof für viele RatschlÄge und die freundliche Unterstützung seitens des Institutes für Physiologie, und Herrn Prof. R. Kuhn für die Durchsicht der Arbeit. Wir versÄumen nicht, der von Portheim-Stiftung wie auch der Dixon Fund der Universität London fìr die GewÄhrung von Stipendien unseren Dank auszusprechen. 相似文献
149.
Bateman DN 《PLoS medicine》2008,5(2):e58
150.
Metabolism of polyadenylic acid sequences during germination of blastocladiella emersoni: Zoospores.
The metabolism of the poly(A) sequences isolated from Blastocladiella emersonii was followed during the first hour of germination. Poly (A) sequences synthesized during the first 30 min of germination do not undergo detectable changes in size. During the first 45 min of germination, poly(A) sequences synthesized during zoosporogenesis decrease in size to the extent that there is essentially no size overlap between poly(A) fragments which were present in the zoospore and newly synthesized poly(A) sequences. The results presented indicate that during germination, polyadenylation occurs in RNA molecules which were present in the zoospore but lacked poly(A) sequences. No detectable size differences were observed between poly(A) sequences added to newly synthesized RNA compared to those added to the nonpolyadenylated RNA present in the zoospore during germination. Cycloheximide did not prevent the observed decrease in size of the poly(A) sequences during germination. 相似文献