Screening, characterization and specific binding mechanism of aptamers against human plasminogen Kringle 5.

Plasminogen Kringle 5 is one of the most potent cytokines identified to inhibit the proliferation and migration of vascular endothelial cells. Herein, six aptamer candidates that specifically bind to Kringle 5 were generated by the systematic evolution of ligands by exponential enrichment (SELEX). After 10 rounds of screening against Kringle 5, a highly enriched ssDNA pool was sequenced and the representative aptamers were subjected to binding assays to evaluate their affinity and specificity.

Molecular recognition and binding of CcrA from Bacteroides fragilis with cefotaxime and ceftazidime by fluorescence spectra and molecular docking.

In search of new super-bacterial inhibitor agents, the recognition and binding mechanism of the B1 subclass MβL CcrA from Bacteroides fragilis with cefotaxime (CTX) and ceftazidime (CAZ) were studied using spectroscopy analysis and molecular docking. The results showed that the fluorescence quenching of CcrA induced by CTX and CAZ were all due to the complex formation, which belonged to static quenching and was forced by hydrogen bonds and Van der Waals forces, despite the greater binding ability of CTX with CcrA than CAZ. Upon recognizing CTX or CAZ, the CcrA opened its binding pocket by the microenvironmental and conformational of three loops changing to promote an induced-fit of the freshly introduced antibiotics.

Screening and identification of bioactive components resistant to metallo-beta-lactamase from Schisandra chinensis (Turcz.) Baill. by metalloenzyme-immobilized affinity chromatography.

The screening and identification of bioactive components, which are effectively resistant to metallo-beta-lactamase (MβL), were studied in the alcohol extract of Schisandra chinensis (Turcz.) Baill. by metalloenzyme-immobilized affinity chromatography.

An illustrated key to the species of subgenus Gyrostoma Kirby, 1828 (Hymenoptera, Vespidae, Polistinae) from China, with discovery of Polistes (Gyrostoma) tenuispunctia Kim, 2001.

The Chinese species of the subgenus Gyrostoma Kirby, 1828 of the polistine genus Polistes are reviewed. An illustrated key to the seven species of the subgenus known from China is given. New synonymy are proposed for Polistes rothneyi Cameron, 1900 =P.