To investigate quantitatively the effects of stirring on protein crystallization, a new stirring system which can agitate a protein solution, approximately 100 nl, by providing Hagen-Poiseuille flow has been successfully developed. In addition, this new stirring system provides flow with a well defined pattern and velocity. Using this system, hen egg-white lysozyme was crystallized in 100-200 n...

It is demonstrated that standard in-house protein crystal X-ray diffraction apparatus can be used to measure very low resolution reflections with only a few modifications. The apparatus and modifications are described in detail and tested on two different macromolecular crystal samples: lysozyme and the 30S ribosomal subunit. Contrast-variation measurements on tetragonal hen egg-white lysozyme ...

Conformational features of reduced and disulfide intact hen egg white lysozyme in aqueous 1,4-dioxane and 3-chloro-1, 2-propanediol solutions have been examined using circular dichroism and fluorescence spectroscopy. We find that in presence of 1, 4-dioxane, reduced lysozyme assumes a relatively compact conformational form with secondary structure closer to native state and no tertiary structur...

Time-resolved CIDNP and Laser Flash Photolysis have been applied to the investigation of the kinetics and mechanism of CIDNP formation in the reactions of aza-aromatic dye 2,2′-dipyridyl and protein-related molecules, including N-acetyl derivatives of three amino acids (tryptophan, tyrosine, histidine) the dipeptide tryptophan-tyrosine, and hen egg-white lysozyme in native and denatured states....

A Monte Carlo algorithm that searches for the optimal docking configuration of hen egg white lysozyme to an antibody is developed. Both the lysozyme and the antibody are kept rigid. Unlike the work of other authors, our algorithm does not attempt to explicitly maximize surface contact, but minimizes the energy computed using coarse-grained pair potentials. The final refinement of our best solut...

The allergy-preventive activity of a 35% EtOH extract (IT) of flowers of Impatiens textori MIQ. was demonstrated in a continuing search for allergy-preventive substances from natural sources. The evaluation of its activity used an in vivo assay method for monitoring the blood flow decrease in the tail vein microcirculation of mice subjected to sensitization with hen-egg white lysozyme. Among th...

A microscope for quantitative analysis of the birefringence properties of samples is introduced. The microscope is used to measure variations in the slow optical axis position (SOAP) across hen egg-white lysozyme, glucose isomerase and fibronectin crystals. By comparing these variations with indicators of diffraction quality, it is shown that the optical properties of a protein crystal provide ...

The effect of coupling the salt concentration gradient crystallization method with the use of the paramagnetic salt MnCl(2) and a magnetic field is reported. The use of a simple magnetic device is proposed to have a significant effect on hen egg-white lysozyme crystal growth. Large single crystals greater than 10 mm(3) in volume with optical perfection were consistently obtained in this study.

Hen egg white lysozyme, fully inactivated by the affinitylabeling reagent, the 2’,3’-epoxypropyl fl-glycoside of di-(NaCetyl-D-glUCOSamine), contained 1 mole of the label per mole of protein. Total enzymatic digestion of the reduced and carboxymethylated affinity-labeled enzyme afforded, as a major radioactive product, a compound composed solely of aspartic acid and glucosamine at the molar rat...

Several diverse proteins are found to readily dissolve in neat low-transition-temperature mixtures (LTTMs). They undergo no irreversible denaturation in such unusual solvents, and the resistance of hen egg-white lysozyme against thermoinactivation in LTTMs is greater than in aqueous solution at extreme pHs. Separately, the water-sensitive drug aspirin is found to form concentrated transparent L...