Reaction of [Au2(dppa)Cl2] with AgOTf in dichloromethane medium followed ligand addition leads to [Au2(dppa)(RaaiR)](OTf) [RaaiR = p-R-C6H4-N=N-C3H2-NN-1-R, (1-3), abbreviated as N,N-chelator, where N(imidazole) and N(azo) represent N and N, respectively; R = H (a), Me (b), Cl (c) and R = Me (1), CH2CH3 (2), CH2Ph (3), OSO2CF3 is the triflate anion, dppa is diphenylphosphinoammine ring]. The ma...

MacFabe et al. have proposed a novel rat model of autism spectrum disorders (ASDs) with intraventricular infusions of propionic acid (PPA), a gut bacterial metabolic end product and common food preservative, which produces reversible behavioural and electrographic effects coupled with increased oxidative stress and innate neuroinflammatory changes consistent with findings in ASD patients. PPA a...

The peptide transporter from a cold-adapted bacterium has never been reported. In the present study, the dpp operon from the psychrophilic bacterium Pseudoalteromonas sp. strain SM9913 was cloned and analyzed. The dipeptide binding protein DppA of SM9913 was overexpressed in Escherichia coli, and its cold adaptation characteristics were studied. The recombinant DppA of SM9913 (PsDppA) displayed...

A survey was carried out in France in 1999 in a Densely Populated Pig Area (DPPA) and a Sparsely Populated Pig Area (SPPA) from which 80 and 55 pig farms were respectively investigated. The two areas were compared regarding the number of respiratory disease outbreaks in fattening pigs on each farm per year with a multiple correspondence analysis and hierarchical clustering. The two areas exhibi...

A polypodal ligand based on an aromatic ring decorated by four dppa-type diphosphine moieties has been used to prepare Pt(II) complexes and to assemble four tricobalt or tetracobalt carbonyl clusters, leading to centrosymmetric Co12 and Co16 "clusters of clusters" which were characterized by X-ray diffraction.

The synthesis of cyclic RGD peptides with 8-10 residues cyclized by an amide bond and the relationship between their structure and activity (i.e. circular dichroism spectrum and inhibition of platelet aggregation) are reported. The linear peptides were synthesized by the solution method and their cyclization was performed in high dilution using DPPA.

Streptococcus agalactiae is a major cause of invasive infections in human newborns. To satisfy its growth requirements, S. agalactiae takes up 9 of the 20 proteinogenic amino acids from the environment. Defined S. agalactiae mutants in one or several of four putative peptide permease systems were constructed and tested for peptide uptake, growth in various media, and expression of virulence tra...

In Escherichia coli, the gcvB gene encodes a nontranslated RNA (referred to as GcvB) that regulates OppA and DppA, two periplasmic binding proteins for the oligopeptide and dipeptide transport systems. An additional regulatory target of GcvB, sstT, was found by microarray analysis of RNA isolated from a wild-type strain and a gcvB deletion strain grown to mid-log phase in Luria-Bertani broth. T...