Towards a biologically

The K103N substitution is a frequently observed HIV-1 RT mutation in patients who do not respond to combinationtherapy. The drugs Efavirenz, MSC194 and PNU142721 belong to the recent generation of NNRTIs characterized by an improved resistance profile to the most common single point mutations within HIV-1 RT, including the K103N mutation. In the present study we present structural observations from Efavirenz in complex with wild-type protein and the K103N mutant and PNU142721 and MSC194 in complex with the K103N mutant.

8p system191 01-06-2013 41 4   Download

Human glandular kallikrein 2 (hK2) is a trypsin-like serine protease expressed predominantly in the prostate epithelium. Recently, hK2 has proven to be a useful marker that can be used in combination with prostate specific antigen for screening and diagnosis of prostate cancer. The cleavage by hK2 of certain substrates in the proteolytic cascade suggest that the kallikrein may be involved in prostate cancer development; however, there has been very little other progress toward its biochemical characterization or elucidation of its true physiological role.

8p system191 01-06-2013 45 2   Download

Four substrate analogs, 4-(2-naphthyloxy)-2-butyn-1-amine (1), 1,4-diamino-2-chloro-2-butene (2), 1,6-diamino-2,4hexadiyne (3), and 2-chloro-5-phthalimidopentylamine (4) have been tested as inhibitors against mammalian, plant, bacterial, and fungal copper-containing amine oxidases: bovine plasma amine oxidase (BPAO), equine plasma amine oxidase (EPAO), pea seedling amine oxidase (PSAO), Arthrobacter globiformis amine oxidase (AGAO), Escherichia coli amine oxidase (ECAO), and Pichia pastoris lysyl oxidase (PPLO).

14p research12 01-06-2013 43 6   Download

The prokaryotic ATP-citrate lyase is considered to be a key enzyme of the carbon dioxide-fixing reductive tricarboxylic acid (RTCA) cycle. Kinetic examination of the ATP-citrate lyase from the green sulfur bacterium Chlorobium limicola (Cl-ACL), an a4b4 heteromeric enzyme, revealed that the enzyme displayed typical Michaelis-Menten kinetics toward ATP with an apparent Km value of 0.21 ± 0.04 mM. However, strong negative cooperativity was observed with respect to citrate binding, with a Hill coefficient (nH) of 0.45. ...

8p research12 01-06-2013 41 4   Download

A cellulase [endo-b-1,4-D-glucanase (EC 3.2.1.4)] was iso-lated from the hepatopancreas of abalone Haliotis discus hannaiby successive chromatographies on TOYOPEARL CM-650M, hydroxyapatite and Sephacryl S-200 HR. The molecular mass of the cellulase was estimated to be 66 000 Da by SDS/PAGE, thus the enzyme was named HdEG66. The hydrolytic activity of HdEG66 toward carb-oxymethylcellulose showed optimal temperature and pH at 38
Cand 6.3, respectively.

8p tumor12 20-04-2013 45 4   Download

The benzoacronycine derivative, S23906-1, was character-ized recently as a novel potent antitumor agent through alkylation of theN2 positionof guanines inDNA.We show here that its reactivity towards DNA can be modulated by glutathione (GSH). The formation of covalent adducts between GSH and S23906-1 was evidenced by EI-MS, and the use of different GSH derivatives, amino acids and dipeptides revealed that the cysteine thiol group is absolutely required for complex formation because glutathione disul-fide (GSSG) and other S-blocked derivatives failed to react covalently with S23906-1. ...

12p fptmusic 16-04-2013 41 4   Download

To elucidate the structural features of the mussel defensin MGD1 required for antimicrobial activity, we synthesized a series of peptides corresponding to the main known secon-dary structures of the molecule and evaluated their activity towards Gram-positive and Gram-negative bacteria, and filamentous fungi. We found that the nonapeptide corres-ponding to residues 25–33 of MGD1 (CGGWHRLRC) exhibited bacteriostatic activity once it was cyclized by a non-naturally occurring disulfide bridge.

9p fptmusic 16-04-2013 47 2   Download

The newly emerging field of systems biology involves a judicious interplay between high-throughput ‘wet’ experimentation, computational modelling and technology development, coupled to the world of ideas and theory. This interplay involves iterative cycles, such that systems biology is not at all confined to hypothesis-dependent studies, with intelligent, principled, hypothesis-generating studies being of high importance and consequently very far from aimless fishing expeditions.

22p inspiron33 26-03-2013 37 5   Download

The vascular network of the brain is formed by the invasion of vascular sprouts from the pia mater toward the ventricles. Following angiogenesis of the primary vascular network, brain vessels experience a maturation pro-cess known as barriergenesis, in which the blood–brain barrier is formed.

14p vinaphone15 25-02-2013 32 3   Download

Carotenoids are widespread terpenoid pigments with applications in the food and feed industries. Upon illumination, the gibberellin-producing fun-gusFusarium fujikuroi(Gibberella fujikuroimating population C) develops an orange pigmentation caused by an accumulation of the carboxylic apoc-arotenoid neurosporaxanthin.

16p vinaphone15 25-02-2013 34 5   Download

During cell intoxication by diphtheria toxin, endosome acidification trig-gers the translocation of the catalytic (C) domain into the cytoplasm. This event is mediated by the translocation (T) domain of the toxin. Previous work suggested that the T domain acts as a chaperone for the C domain during membrane penetration of the toxin.

10p cosis54 04-01-2013 37 4   Download

We previously reported the construction and activity of a humanized, bispecific diabody (hEx3) that recruited T cells towards an epidermal growth factor receptor (EGFR) positive tumor. Herein, we describe the construction of a second functional, fully humanized, anti-EGFR bispecific diabody that recruits another subset of lymphocyte effectors, the natural killer cells, to EGFR-expressing tumor cells.

11p cosis54 08-12-2012 41 3   Download

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí y học Molecular Biology cung cấp cho các bạn kiến thức về ngành sinh học đề tài: A spatio-temporal mining approach towards summarizing and analyzing protein folding trajectories...

16p hoami_2511 21-10-2011 47 4   Download

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Functions of O-fucosyltransferase in Notch trafficking and signaling: towards the end of a controversy?

5p toshiba3 07-09-2011 45 4   Download