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1.
Maria V. Sergeeva Vadim V. Mozhaev Joseph O. Rich Yuri L. Khmelnitsky 《Biotechnology letters》2000,22(17):1419-1422
A novel biocatalytic reaction of transamidation of non-activated amides with amines is reported. Among 45 different lipolytic and proteolytic enzymes tested, only the lipase from Candida antarcticawas able to catalyze this reaction. The reaction proceeded with up to ca. 80% conversion in anhydrous methyl tert-butyl ether and worked with both N-substituted and unsubstituted amides. The biocatalytic transamidation is an equilibrium process and, therefore, higher conversions to the desired amide were achieved by using increased concentrations of the amine nucleophile. 相似文献
2.
Seabirds are affected by changes in the marine ecosystem. The influence of climatic factors on marine food webs can be reflected in long-term seabird population changes. We modelled the survival and recruitment of the Mediterranean storm petrel (Hydrobates pelagicus melitensis) using a 21-year mark-recapture dataset involving almost 5000 birds. We demonstrated a strong influence of prebreeding climatic conditions on recruitment age and of rainfall and breeding period conditions on juvenile survival. The results suggest that the juvenile survival rate of the Mediterranean subspecies may not be negatively affected by the predicted features of climate change, i.e., warmer summers and lower rainfall. Based on considerations of winter conditions in different parts of the Mediterranean, we were able to draw inferences about the wintering areas of the species for the first time. 相似文献
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Yoko Yamauchi Hikari Kimoto Xianyu Yang Sergey Filkin Yuri Utkin Tai Kubo 《Bioscience, biotechnology, and biochemistry》2016,80(1):158-161
Three-finger toxins (3FTxs) are one of the major components in snake venoms. In this study, we isolated a cDNA encoding a short-chain 3FTx, Pr-SNTX, from Pseudechis rossignolii. The amino acid sequence of Pr-SNTX is nearly identical to that of its ortholog in Pseudechis australis. Pr-SNTX protein inhibited muscle-type (α2βδε), but not neuronal α7 nicotinic acetylcholine receptor (nAChR) activity. 相似文献
5.
R R Kantor M J Mattes K O Lloyd L J Old A P Albino 《The Journal of biological chemistry》1987,262(31):15158-15165
Two mouse monoclonal antibodies (mAb), AJ2 and J143, define two related human cell surface protein complexes, very common antigen 1 (VCA-1) and very common antigen 2 (VCA-2). In the present report, these complexes have been defined with respect to: (i) subunit arrangement; (ii) monoclonal antibody binding sites; (iii) carbohydrate content; (iv) homology to other cell surface protein complexes; and (v) possible functional roles. Analysis of the antigens from a human melanoma cell line, MeWo, reveals that VCA-1 is a noncovalently linked heterodimer of 170- and 140 (designated 1401)-kDa polypeptides. mAb AJ2 reacts with an epitope on the 1401-kDa polypeptide. VCA-2 is composed of the same 1401-kDa polypeptide as VCA-1 and another 170-kDa species; this 170-kDa species consists of a second distinct 140-kDa (designated 140(2)) and a 30-kDa polypeptide which are disulfide-bonded. Indirect evidence indicates that mAb J143 reacts with an epitope on this 170-kDa complex. Peptide mapping has shown that the complexes are members of a family of cell surface proteins that include antigens present on activated T cells (designated very late activation antigens). Since VCA-2 is found predominantly on the basal membrane of adherent cells and its expression increases 12-fold when HUT-102 lymphoblastoid cells are grown as an adherent cell culture, we suggest that VCA-2 plays a role in cellular adherence. 相似文献
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Summary High yields of protoplasts were obtained from leaves of aseptically grown plants and calli originated from different explants, in several cultivars of Cajanus cajan L. The protoplasts divided to form cell clusters in modified KM 8p medium and developed to protocolonies after dilution with liquid Caboche's medium within three to four weeks of culture. The protocolonies proliferated to form green calli on solid Caboche's medium. No shoots or plants were obtained.Abbreviations BAP
6-benzylaminopurine
- NAA
-napthaleneacetic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- Kin
kinetin
- Zea
zeatin
- Adn S
adenine sulphate
- GA 3
gibberellic acid 相似文献
9.
Kaijiro Anzai Shunsuke Kobayashi Narumi Kitamura Yuri Kanai Hiromichi Nakajima Yoshioki Suehiro Sataro Goto 《Journal of neurochemistry》1986,47(3):673-677
We isolated a mouse genomic clone that hybridized with small RNA present in the cytoplasm of the brain. The RNA was about 150 nucleotides long. This RNA seemed to be specific to the brain, since it was not found in the liver or kidney. The clone DNA contained a sequence homologous to 82-nucleotide "identifier" core sequence of cDNA clones of rat. The sequence contained a split promoter for RNA polymerase III and was flanked by a 12-nucleotide direct repeat (ATAAATAATTTA). 相似文献
10.
The synthesis of a fluorescent lipid for use in studies of immune recognition of model membranes is described. The molecule has the basic structure HAPTEN-SPACER-LIPID, where fluorescein is the hapten, an oligopeptide (triglycine) is the spacer, and dipalmitoylphosphatidylethanolamine (DPPE) is the lipid. The spacer, which is necessary for immunological reactivity, is first linked via a peptide bond to DPPE. The free N-terminus of the peptidyl-DPPE is then reacted with 5-dichlorotriazinylaminofluorescein (DCTAF) to yield fluoresceinchlorotriazinyltriglycyl-DPPE (FG3P). The structure is confirmed by mass spectrometry and Fourier transform NMR. When FG3P is incorporated into phospholipid vesicles it retains the brilliant fluorescence and high-affinity immunological reactivity of fluorescein. The general synthesis scheme may prove useful in other membrane and lipoprotein applications. 相似文献