A study of gas transport properties of novel polynorbornenes with increasing length of an aliphatic pendant group R (CH3{, CH3(CH2)3{, CH3(CH2)5{, CH3(CH2)9{) has been performed. These polymers were synthesized using novel organometallic complex catalysts via an addition polymerization route. This reaction route maintained the bridged norbornene ring structure in the final polymer backbone. Gas...

Microtubule structure and functions have been widely studied in vitro and in cells. Research has shown that cysteines on tubulin play a crucial role in the polymerization of microtubules. Here, we show that blocking sulfhydryl groups of cysteines in taxol-stabilized polymerized microtubules with a commonly used chemical crosslinker prevents temporal end-to-end annealing of microtubules in vitro...

The yellow colored sulfhydryl reagent, iV-(4-dimethylamino-3,!%dinitrophenyl)maleimide, was used in the isolation of the peptide containing the reactive sulfhydryl group of chymopapain. Titration of cyanide-activated chymopapain B with p-chloromercuribenzoate at pH 4.6 indicated that there is a maximum of 1.4 moles of sulfhydryl per mole of the enzyme. Alkylation of half of the p-chloromercurib...

Different Interfacial Behaviors of Peptides Chemically Immobilized on Surfaces with Different Linker Lengths and via Different Termini Report Title Molecular structures such as conformation and orientation are crucial in determining the activity of peptides immobilized to solid supports. In this study, sum frequency generation (SFG) vibrational spectroscopy was applied to investigate such struc...

1. The preparation of a derivative of pig heart lactate dehydrogenase in which the essential thiol group has been converted into an S-sulpho group is described. The derivative has unchanged s(20,w) and is catalytically inactive. 2. The rate of reaction of the essential thiol group is controlled by a system with a pK>9. 3. The essential thiol group is protected by NADH against reaction with male...

The title compound, C(10)H(6)ClNO(2), has a dihedral angle of 46.46 (5)° between the benzene and maleimide rings. A short inter-molecular halogen-oxygen contact is observed, with a Cl⋯O distance of 3.0966 (13) Å. Both CO groups are involved in two C-H⋯O inter-actions, which gives rise to sheets parallel to (100). In addition, these sheets exhibit a π-π stacking inter-action between the benzene ...

Lactose repressor protein has been modified with N-ethylmaleimide, two N-maleimide spin labels, and an N-maleimide fluorophore. The reaction with repressor cysteine residues has been characterized. Approximately 2 of the 3 eq of cysteine/repressor monomer are reactive toward these reagents. Repressor cysteines are reactive toward these reagents in the order cysteine 140 greater than or equal to...

A readily and rapidly accessible triazine dendrimer was manipulated in four steps with 23% overall yield to give a construct displaying four maleimide groups and DOTA. The maleimide groups of the dendrimer are sensitive to hydrolysis under basic conditions. The addition of up to four molecules of water can be observed via mass spectrometry and HPLC. The evolution in the alkene region of the ¹H-...

The extensive use of avidin and streptavidin in life sciences originates from the extraordinary tight biotin-binding affinity of these tetrameric proteins. Numerous studies have been performed to modify the biotin-binding affinity of (strept)avidin to improve the existing applications. Even so, (strept)avidin greatly favours its natural ligand, biotin. Here we engineered the biotin-binding pock...