Báo cáo khoa học: Site-directed mutagenesis of selected residues at the active site of aryl-alcohol oxidase, an H2O2-producing ligninolytic enzyme pot

... ª 2006 The Authors Journal compilation ª 2006 FEBS Site- directed mutagenesis of selected residues at the active site of aryl-alcohol oxidase, an H 2 O 2 -producing ligninolytic enzyme Patricia ... above model, site- directed mutagenesis and kinetic studies were used to identify the enzyme active site and evaluate the role of some selected...

Ngày tải lên: 07/03/2014, 11:20

... loop at the entrance to the active site (Fig. 1), as the main cleavage sites. Cleavage of the E1a-subunit activated the enzyme, as determined by a decarboxylation assay of the free E1 in the presence ... range of 25 to 85 °C (Fig. 3). The reaction mixture with E1 was incubated for exactly 10 min at the relevant temperature and the catalytic activity at tha...

Ngày tải lên: 20/02/2014, 23:20

... equivalents of Cd 2+ was required for the formation of the Cd 4 a species in 100% abundance. The implications of a noncooperative metal-binding mechanism are that the partially metallated and metal-free ... larger than those for the b domain. Further interpretation of these data resulted in the proposal of positively cooperative metal binding as the primary metallation...

Ngày tải lên: 19/02/2014, 00:20

... motifs [9,10]. The most prominent of these motifs is the DXDXE motif that spans strand 4 of the TIM barrel and includes the glutamate that acts as the catalytic acid. The active site grooves of these ... described well and there is no example of mutational analysis of all of these residues in the same enzyme. To obtain an insight into how the many conserv...

Ngày tải lên: 07/03/2014, 14:20

... transparency [4]. Determining the mechanism of folding and assembly of these proteins is important for understanding how they can form stable transparent structures at high concentrations. The ... more accurately describes the dissociation/unfolding process of d 2 -crystallin. Another possible origin of the discrepancy between the results of Sampaleanu et al. [30] may be...

Ngày tải lên: 08/03/2014, 08:20

... in the blood of the patient. However, the data were difficult to interprete because of the nature of the mutations which were not truncating mutations (a possible aber- rant splicing effect of these ... emphasizing the lack of sensitivity of direct sequencing of lesion DNA. These data established the existence of biallelic somatic and germline mutations, whatever...

Ngày tải lên: 15/03/2014, 10:20

... mechanical (QM) model of the enzyme active site was constructed. It illustrates the reorganization of the hydrogen bond network at the active site, which predetermines the cat- alytic transformations. Several ... to the catalytic efficiency of the enzyme. The energy barrier computed for the first step of acylation (the nucleophilic attack of SerB1) is lo...

Ngày tải lên: 16/03/2014, 01:20

... general inhibition of translation [16,29]. Phosphorylation of eIF2a also stimulates translation of ATF4 [30], a bZIP-like transcription factor that induces the tran- scription of many amino-acid synthetic enzymes, amino-acid ... act cooperatively such that the fate of the cell depends on the balance between the individual UPR pathways. Therefore, disturbance of these fun...

Ngày tải lên: 16/03/2014, 11:20

... phosphorylates b-catenin and stimulates the ubiquitination and protea- somal proteolysis of b-catenin. During activation of the InR pathway, GSK-3 is inactivated, which leads to the accumulation and nuclear ... transfection. The relative intensity of tyrosine autophosphorylation in immunoprecipatated InR-b or EGFR was calculated from the intensity ratio of the phosphorylat...

Ngày tải lên: 16/03/2014, 12:20

... superficial dl~erence in the use of tenses stands the more important one in the basic meaning of the grammatical category of tense. The standard view is that tense in- dicates relative position in ... been sent by their mother to fix the tail v-~hve of the windmilL b. In the great expanse of the prairie where they lived, the high tower of the windmill w...

Ngày tải lên: 18/03/2014, 02:20