Conventional and microwave‐assisted SPPS approach: a comparative synthesis of PTHrP(1–34)NH2

Attracted by the possibility to optimize time and yield of the synthesis of difficult peptide sequences by MW irradiation, we compared Fmoc/tBu MW‐assisted SPPS of 1–34 N‐terminal fragment of parathyroid hormone‐related peptide (PTHrP) with its conventional SPPS carried out at RT. MWs were applied in both coupling and deprotection steps of SPPS protocol. During the stepwise elongation of the resin‐bound peptide, monitoring was conducted by performing MW‐assisted mini‐cleavages and analyzing them by UPLC‐ESI‐MS. Identification of some deletion sequences was helpful to recognize critical couplings and as such helped to guide the introduction of MW irradiations to these stages. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.     

EDU免疫荧光法检测整合素连接激酶（ILK）高表达对新生大鼠心肌细胞DNA合成的影响

目的：通过EDU免疫荧光法观察整合素连接激酶（Integrin-Linked Kinase,mK）在新生大鼠心肌细胞内高表达后对心肌细胞DNA合成的影响。方法：取新生（1-3天内）大鼠原代心肌细胞,培养72小时后随机分为正常对照组、ILK转染组。对照组转染重组腺病毒载体（adeno-GFP）,ILK纽转染重组腺病毒载体＋ILK基因（adeno-ILK）。转然成功后48小时将两组心肌细胞分别通过5-乙基-2-脱氧尿嘧啶核苷（EDU）免疫荧光法测定心肌细胞DNA合成。结果：ILK转染组心肌细胞内DNA合成较对照组明显增加（P〈O．05）。结论：ILK高袁达具有促进新生大鼠心肌细胞的DNA合成的能力。     

Complete genome sequence of the halophilic and highly halotolerant Chromohalobacter salexigens type strain (1H11(T))

Chromohalobacter salexigens is one of nine currently known species of the genus Chromohalobacter in the family Halomonadaceae. It is the most halotolerant of the so-called 'moderately halophilic bacteria' currently known and, due to its strong euryhaline phenotype, it is an established model organism for prokaryotic osmoadaptation. C. salexigens strain 1H11(T) and Halomonas elongata are the first and the second members of the family Halomonadaceae with a completely sequenced genome. The 3,696,649 bp long chromosome with a total of 3,319 protein-coding and 93 RNA genes was sequenced as part of the DOE Joint Genome Institute Program DOEM 2004.     

EDU 免疫荧光法检测整合素连接激酶（ILK）高表达 对新生大鼠心肌细胞DNA 合成的影响

目的:通过EDU免疫荧光法观察整合素连接激酶(Integrin-Linked Kinase,ILK)在新生大鼠心肌细胞内高表达后对心肌细胞DNA合成的影响。方法:取新生(1-3天内)大鼠原代心肌细胞,培养72小时后随机分为正常对照组、ILK转染组。对照组转染重组腺病毒载体(adeno-GFP),ILK组转染重组腺病毒载体+ILK基因(adeno-ILK)。转然成功后48小时将两组心肌细胞分别通过5-乙基-2’-脱氧尿嘧啶核苷(EDU)免疫荧光法测定心肌细胞DNA合成。结果:ILK转染组心肌细胞内DNA合成较对照组明显增加(P<0.05)。结论:ILK高表达具有促进新生大鼠心肌细胞的DNA合成的能力。     

Effect of litter size and bacitracin administration on tissue protein synthesis of lactating rabbit does

Bacitracin is an antibiotic used in rabbit husbandry to control microbial digestive pathologies. Collateral effects on absorption and mucosal development have been reported and these may impact on protein metabolism. This study aims to analyse the effect of the antibiotic on protein synthesis in lactating does because mammary gland metabolism and milk output should provide a sensitive index of any undesirable action of bacitracin. Rates of protein synthesis were measured in mammary gland, liver, intestinal mucosa and muscle of lactating rabbits does by injecting a flooding dose of [(2)H(5)]phenylalanine into the auricular artery of two groups (each n = 8) of New Zealand White does fed different experimental diets. The control group (C) received the basal diet and the bacitracin group (B) ingested the same diet but supplemented with bacitracin (100 mg/kg). Animals received the experimental diet from day 28 of pregnancy until day 26 of lactation when they were slaughtered. Just after birth, litter size was adjusted by cross-fostering either to five or nine pups (four does per dietary treatment). The relative weight of the liver tended to be greater in those females receiving the B diet (27 v. 22.5 g/kg BW; P < 0.07), while diet did not affect mammary gland weight (255.7 ± 10.59 g). Fractional protein synthesis rate (FSR) was higher for intestinal mucosa (duodenum; 51.7% ± 2.09%/day) followed by mammary gland and liver (38.29 ± 2.62%/day and 40.2 ± 1.98%/day, respectively), and the lowest value was observed in muscle (2.92 ± 0.26%/day; P < 0.0001). Bacitracin treatment lowered FSR in the mammary gland by 23% (P = 0.024) and this was independent of litter size. Conversely, FSR in the duodenum was not affected by antibiotic treatment but reduced by 15% (P = 0.021) for the larger litter size.     

A combinatorial approach to the synthesis of cystine based organogelators.

A solid-phase approach was used to prepare 20 cystine amide derivatives with disulfide bond formation resulting from an intra-site reaction between neighbouring cysteine residues. Library members were screened as potential organogelators in a range of solvent mixtures and resulted in the identification of a potent gelator able to rigidify water/DMSO mixtures at concentrations as low as 1.3 mM.     

Synthesis of hepcidin derivatives in order to develop standards for immune adsorption method

MeCN, acetonitrile; ECL, enhanced chemiluminescence; EDT, 1,2‐ethanedithiole; HEPC12‐A, rabbit anti‐human hepcidin IgG, affinity purified; HEPC13‐A, rabbit anti‐mouse/human hepcidin IgG, affinity purified; HEPC61‐P, human hepcidin‐25 control/blocking synthetic peptide; HRP, horseradish peroxidase; IL‐6, interleukin‐6; KLH, keyhole limpet hemocyanin; LEAP, liver‐expressed antimicrobial peptide; NEM, N‐ethylmaleimide; NMP, N‐methyl‐pirrolidone; PBS, phosphate buffered saline; PVDF, polyvinylidene difluoride; SELDI‐TOF‐MS, surface‐enhanced laser desorption ionization–time‐of‐flight mass spectrometry; TMB, tetramethylbenzidin; TNF‐α, tumor necrosis factor‐α Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.     

Enzymatic formation of intermediates in the biosynthests of ajmalicine: Strictosidine and cathenamine

Pre-purified enzymes isolated from Catharanthus roseus suspension cultures synthesize strictosidine and cathenamine from tryptamine and secologanin. Whereas strictosidine showed metabolic activity, cathenamine accumulates during the cell-free incubations in the absence of reduced pyridine nucleotides. In the presence of δ-d-gluconolactone (0.1 M), strictosidine accumulates in a yield of ca 50%. Optimum conditions for its accumulation in crude extracts were found to be at pH 4.1, 0.25 mM tryptamine and 1.25 mM secologinin. Strictosidine synthase is stable for more than 1.5 months at 4°. The optimum conditions for the enzymatic synthesis of cathenamine are 1.54 mM tryptamine and 7.7 mM secologanin at pH 7.5. In the presence of NH₄⁺ the formation of the latter alkaloid decreases due to the synthesis of unidentified compounds.