Investigation of the effect of homocysteinylation of substance P on its binding to the NK1 receptor using molecular dynamics simulation.

Substance P is a neurotransmitter or modulator in both the central and peripheral nervous systems. In this work, modifications of the lysine in SP by homocysteine and an acetyl group as well as the conformational dynamics of the native and modified SP peptides and their complexes with the NK1 receptor were studied via MD simulation. It was found that modifying SP stabilizes the peptide structure, but the modified SP peptides are less likely to bind to the NK1 receptor, so the resulting complexes are less stable.

Process development for production of human granulocyte-colony stimulating factor by high cell density cultivation of recombinant Escherichia coli.

The fed-batch process using glucose as the sole source of carbon and energy with exponential feeding rate was carried out for high cell density cultivation of recombinant Escherichia coli BL21 (DE3) expressing human granulocyte-colony stimulating factor (hG-CSF). IPTG was used to induce the expression of hG-CSF at 48 g dry cell wt l(-1) during high cell density culture of recombinant E. coli BL21 (DE3) [pET23a-g-csf].

Improving purification of recombinant human interferon gamma expressed in Escherichia coli; effect of removal of impurity on the process yield.

Process development and optimization studies were performed in order to improve the purification process of (rhIFN-gamma). The objective was to generate material with higher purity and quantity. An in-process control screening was developed to obtain the optimal condition for column chromatographic purification by measuring LPS, nucleic acids, rhIFN- gamma, monomer and its covalent dimers.

Effect of oxidative stress on the production of recombinant human interferon-gamma in Escherichia coli.

To reduce the degradation pathway of rhIFN-gamma (recombinant human interferon-gamma), the susceptibility against oxidative stress during fermentation in Escherichia coli cells and in purification process were investigated. Fermentations of recombinant E. coli were performed at 5, 30 and 60% DO (dissolved oxygen) concentrations.