Báo cáo khoa học: Kinetics of enzyme acylation and deacylation in the penicillin acylase-catalyzed synthesis of b-lactam antibiotics pptx

... the kinetic constants forhydrolysis and synthesis of penicillin G, ampicillin and cephalexin. Furthermore, insight into the nature of the transition state in the rate-determining steps of the ... Kinetics of enzyme acylation and deacylation in the penicillin acylase-catalyzed synthesis of b-lactam antibiotics Wynand B. L. Alkema, Erik de Vries, Rene´Floris and Dick B. JanssenDepartment ... strength and pH eﬀects in the kinetically controlled synthesis of benzylpenicillin byTable 2. Kinetic constants for synthesis and hydrolysis of b-lactam antibiotics by penicillin acylase. The rate and...

Báo cáo khoa học: "Some Comments on Algorithm and Grammar in the Automatic Parsing of Natural Languages" ppt

... written in the form of appropriate tables of rules. The paper raises the question of the increasing complexity of the tables when more than the most elementary natural-language con- ditions are included, ... Examples of this are very common in English and include many of the frequently cited instances of nesting. The second consideration is that the determination of external functioning by con- ... attention to the parsing problems encoun- tered in machine translation. It must be noted at the outset that in this author’s opinion the aim of the automatic-parsing component of a machine-translation...

Báo cáo khoa học: Accessory proteins functioning selectively and pleiotropically in the biosynthesis of [NiFe] hydrogenases in Thiocapsa roseopersicina docx

... protein, likely to be involved in the processing of the HupL subunit [15]. It is plausible toassume that HynD is involved in the maturation of the HynL protein. Indeed, in the strain harboring the ... acidresidues in the truncated HupK originated from the N-terminus, 37 aa from the C-terminus of the protein and 13 aa came from the multiple cloning site of the pK18mob-sacB vector. The extensively ... not in the bio- synthesis of the soluble enzyme. In- frame deletion muta-genesis showed that HypC proteins were not speciﬁc for the maturation of either hydrogenase enzyme. The lack of eitherHypC...

Báo cáo khoa học: "A Tradeoff between Compositionality and Complexity in the Semantics of Dimensional Adjectives" potx

... knowledge base. Thus in the present paper, I investigate the kinds of relations that appear in formal theories of the meanings of the following morphosyntactic con- structions of dimensional adjectives: ... lengths of all of the constraints) * May not terminate if the system is inconsistent tTerminates in arbitrarily long (finite) time if the system is inconsistent tMay not terminate if the solution ... replacing x~ in L With the upper bound of REFINE(Cj, Xi, L). We say that these refinements are based on Cj. If the upper and lower bounds of REFINE are computable, then refinement is by definition...

Báo cáo khoa học: Myocyte enhancer factor 2B is involved in the inducible expression of NOX1⁄ NADPH oxidase, a vascular superoxide-producing enzyme ppt

... arrows.(B) The exon ⁄ intron structure of the NOX1gene and its splicing pathway. Open boxesindicate exons. Numbers in the box denote the size of each exon (bp). The size of the intron is indicated ... affect the mobility of the speciﬁc bands (lane 4, Fig. 4B). These resultssuggest that PGF2aincreases the binding of MEF2to the consensus-binding site located between )139 and )130 of the NOX1 ... whereas the bandswere undetectable in the presence of an excess amount of the unlabeled wild-type probe (lane 3). By contrast, the bands persisted in the presence of an excess amount of the mutated...

Tài liệu Báo cáo khoa học: An immunomodulator used to protect young in the pouch of the Tammar wallaby, Macropus eugenii pptx

... euge-nin, indicating that eugenin is indeed acting throughCCK2receptors.To further investigate the interaction of eugenin withCCK2receptors, we investigated the effect of eugeninon lymphocyte ... asstimulation of the proliferation of lymphocytes, activa-tion of CCK receptors stimulate production of inter-leukins and secretion of immunoglobulins on the mucosal surface of the intestine [49,50]. The ... temperature with only minimal damage to the Tyr(SO3) residue [31,32]. The procedure used for the synthesis of eugenin is a modiﬁcation of the reportedmethods, and is outlined in detail in Experimental...

Tài liệu Báo cáo khoa học: "Using adaptor grammars to identify synergies in the unsupervised acquisition of linguistic structure" docx

... We initialize the sampler by randomly as-signing each string in the training corpus a randomtree generated by the grammar. Then we randomlyselect a string to resample, and sample a parse of ... terminal in the grammar. If Ais a terminal then GAis the distribution that puts all of its mass on the unit tree (i.e., tree consisting of asingle node) labeled A. If A is a nonterminal thenGAis ... grammar, in which the subtrees are speciﬁed in advance, in an adaptor grammar the subtrees, aswell as their probabilities, are learnt from the train-ing data. In order to make parsing and inferencetractable...

Báo cáo khoa học: Cytosolic phospholipase A2-a and cyclooxygenase-2 localize to intracellular membranes of EA.hy.926 endothelial cells that are distinct from the endoplasmic reticulum and the Golgi apparatus pdf

... structures resembling the Golgi, with very little staining in the region of the nuc-lear membrane. In addition, a highly punctate stainingpattern throughout the cytosol and nucleus of a restingcell ... 0.05% digitonin,very little nuclear staining was evident in resting cells(Fig. 3A). Following stimulation with A23187, the intensity of staining of the nuclear membrane in digito-nin-permeabilized ... in the level of staining when usingdigitonin instead of Triton X-100 (Fig. 3C). Such adecrease suggests that some relocation is occurring to the inner surface of the nuclear membrane, where the cPLA2-a...

Báo cáo khoa học: A novel serine protease highly expressed in the pancreas is expressed in various kinds of cancer cells potx

... conﬁrm the expression of proseminmRNA in some cell lines. A band of the predicted size(500 bp) of the PCR product was observed for most of the cell lines tested, including HPC-YO and HPC-YS, in ... Black bars indicate the enzymatic activity of entero-kinase on the substrate. The closed circles and line indicate prosemin enzyme activity after activation of the protein by enterokinase; the enzymatic ... kinds of cancer cell lines and in clinical samples of ovarian carcinomas. The characteri-zation and functions of prosemin are described.ResultscDNA cloning and structure of the prosemingeneWe...

Báo cáo khoa học: Factor-inhibiting hypoxia-inducible factor (FIH) catalyses the post-translational hydroxylation of histidinyl residues within ankyrin repeat domains pot

... 239FIH). Instead the imidazole ring is sand-wiched between the side chains of His 199FIHthatforms part of the catalytic triad and the aromaticring of Tyr 102FIH. The side chain of Gln 239FIHmoves ... that of Asn and Asp hydroxylations.Fig. S6. The presence of b-hydroxyhistidine in the gly-copeptide antibiotic bleomycin.Fig. S7. Biosynthesis of b-hydroxyhistidine found in nikkomycin antibiotics. Table ... possiblyreﬂecting that in the ankyrin repeat (AR) of the parenttankyrase ARD protein (Fig. 5A). At the active site, the Fe(II) and 2OG are bound as ﬁrst reported for the structure of FIH in complex...

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