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991.
Kenneth J. Rothschild Mark Zagaeski William A. Cantore 《Biochemical and biophysical research communications》1981,103(2):483-489
We report the first Fourier transform infrared difference spectra of purple membrane. Evidence is presented that alterations in the vibrations of both the retinylidene chromophore and the protein groups of bacteriorhodopsin associated with photocycling can be detected. This method provides a new tool for probing the conformational changes occurring in bacteriorhodopsin during the proton pump cycle. 相似文献
992.
993.
994.
Marion H. OLeary William J. DeGooyer Thomas M. Dougherty Vernon Anderson 《Biochemical and biophysical research communications》1981,100(3):1320-1325
1-Hydroxycyclopropane carboxylic acid phosphate has been synthesized from diethyl succinate by acyloin condensation followed by ring contraction and phosphorylation. This compound is a potent competitive inhibitor of enzymes utilizing phosphoenolpyruvate. For phosphoenolpyruvate from maize, Ki = 7.3 μM at pH 8.0 in the presence of Mg2+. For pyruvate kinase, Ki = 2.0 mM at pH 7.0. For enolase, Ki = 8.0 μM at pH 8.0. In each case, this compound is a substantially better inhibitor than the commonly used phosphoenolpyruvate analogs phosphoglycolate and phospholactate, presumably because of the similarity in geometric and electronic structure between the cyclopropane compound and phosphoenolpyruvate. 相似文献
995.
William R. Buck 《Brittonia》1981,33(4):556-563
Eriodon is reduced from five species to two.Eriodon radicalis is recognized asEntodontopsis radicalis;Eriodon longipes asPorotrichodendron longipes; andE. brevisetus as synonymous withLindigia debilis. Mandoniella, Stenocarpidiopsis andLepyrodontopsis are discussed and illustrated.Lepyrodontopsis is transferred to the new familyLe pyrodontopsidaceae, near the Meteoriaceae. The following nomenclatural trans fers are proposed for Rozea:R. andrieuxii f.chrysea andR. andrieuxii var.bour gaeana. Sciuroleskea is transferred to an alliance withStereophyllum,Juratzkaea, Entodontopsis, Stenocarpidium andJuratzkaeella. The following transfers are proposed:Sciuroleskea roseorum (Williams asRozea) Buck andJuratzkaea argentinica (Thér. asJ. seminervis var.argentinica) Buck. A key to the erect-capsuled South American genera retained in the Brachytheciaceae is provided. 相似文献
996.
William R. Buck 《Brittonia》1981,33(3):453-456
Cheilothela Lindb. is recognized as a monotypic genus forC. chloropus (Brid.) Lindb. The South American and New Zealand taxa are considered to be synonymous and placed in the resurrectedChrysoblastella Williams asC. chilensis (Mont.) Reim.Chrysoblastella is segregated fromCheilothela on the basis of numerous sporophytic characters as well as their phytogeography.Cheilothela longirostre Fleisch., from Java, is misplaced in either genus and a new genus,Strombulidens, is erected to accommodate it.Strombulidens is considered most closely related toWilsoniella on the basis of their unique peristomes. 相似文献
997.
The new genusBarnebya is described and illustrated and its systematic position in the Malpighiaceae is discussed, especially its similarity in some respects to the primitive subfamily Byrsonimoideae and in other respects to the Old World genusAcridocarpus. Two species are recognized,B. dispar comb. nov. andB. harleyi sp. nov.; these are described and illustrated and a key is provided for their distinction. 相似文献
998.
Judy M. Goddard Jeffrey N. Masters Suzan S. Jones William D. Ashworth Jr. David R. Wolstenholme 《Chromosoma》1981,82(5):595-609
The mitochondrial DNA (mtDNA) molecules of different albino, domesticated rats (Rattus norvegicus) of the SASCO colony are of two kinds (SASCO-1 and SASCO-2) in regard to their sensitivity at certain sites to a number of restriction enzymes. MtDNA molecules from Utah wild R. norvegicus (Wild-UT) have sensitivities to restriction enzymes which differ at some sites from either SASCO-1 or SASCO-2 mtDNA molecules. Four single nucleotide differences were found among the HindIII F fragments (169 nucleotides) of SASCO-1, SASCO-2, and Wild-UT mtDNAs. Arguments are presented in favor of the interpretation that each variant nucleotide is the third nucleotide of the codon containing it, and that none of the four differences would result in a difference in the respective amino acid translated.Dedicated to Professor W. Beermann on the occasion of his 60th birthday 相似文献
999.
1000.