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991.
An efficient and versatile protocol to incorporate the achiral and C(alpha,alpha)-tetrasubstituted 4-amino-1,2-dithiolane-4-carboxylic acid Adt (1) residue into peptides is described. The 2,2-bis[(benzylthio)methyl]glycine N-carboxy anhydride (5) was found to be the key reactive intermediate from which both Boc-Adt-OMe (8) and the glutathione analogue H-Glu(-Adt-Gly-OH)-OH (12) can be obtained.  相似文献   
992.
A novel thermophilic glycosynthase that effects branching glycosylation   总被引:3,自引:0,他引:3  
A novel thermophilic glycosynthase that effects branching glycosylation has been obtained by mutation of the nucleophile in the active site of the glycosidase from Sulfolobus solfataricus. Two methods for the use of this mutant are reported.  相似文献   
993.
The mechanism during apoptosis by which cytochrome c is rapidly and completely released in the absence of mitochondrial swelling is uncertain. Here, we show that two distinct pathways are involved. One mediates release of cytochrome c across the outer mitochondrial membrane, and another, characterized in this study, is responsible for the redistribution of cytochrome c stored in intramitochondrial cristae. We have found that the "BH3-only" molecule tBID induces a striking remodeling of mitochondrial structure with mobilization of the cytochrome c stores (approximately 85%) in cristae. This reorganization does not require tBID's BH3 domain and is independent of BAK, but is inhibited by CsA. During this process, individual cristae become fused and the junctions between the cristae and the intermembrane space are opened.  相似文献   
994.
Investigations on P(2)-P(3)-heterocyclic dipeptide surrogates directed towards identification of an orally bioavailable thrombin inhibitor led us to pursue novel classes of achiral, non-covalent P(1)-arginine derivatives. The design, synthesis, and biological activity of inhibitors NC1-NC30 that feature three classes of monocyclic P(1)-arginine surrogates will be disclosed: (1) (hetero)aromatic amidines, amines and hydroxyamidines, (2) 2-aminopyrazines, and (3) 2-aminopyrimidines and 2-aminotetrahydropyrimidines.  相似文献   
995.
Gori  A.  Viladrich  N.  Gili  J-M.  Kotta  M.  Cucio  C.  Magni  L.  Bramanti  L.  Rossi  S. 《Coral reefs (Online)》2012,31(3):823-837
Coral Reefs - The annual gonad development of a shallow (20 m depth) population of the Mediterranean gorgonian Eunicella singularis was found to be closely synchronized with that of a deep...  相似文献   
996.
X‐ray atomic structure of recombinant Hell's gate globin I (HGbI) from Methylacidophilum infernorum was calculated from the X‐ray diffraction data of two different types of crystals: obtained by classical hanging drop and by LB nanotemplate method under the same crystallization conditions. After the accurate comparison of crystallographic parameters and electron density maps of two structures they appears to be quite similar, while the quality of the crystals grown by LB nanotemplate method was higher then of those grown by classical method. Indeed, the resolution of the LB crystal structure was 1.65 Å, while classical crystals showed only 3.2 Å resolution. Moreover, the reproducibility of this result in the case of LB crystals was much better—nine crystals from 10 gave the same structural results, while only two of 10 classical crystals were appropriate for the X‐ray structure resolution. J. Cell. Biochem. 113: 2543–2548, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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