Comparison of Antibody Immune responses to different HIV-1 Envelope Glycoprotein Mutants.

The identification of immunogens is crucial for human immunodeficiency virus type 1 (HIV-1) vaccine development. In our previous study, we demonstrated that HIV-1 envelope glycoprotein mutants based on the equine infectious anemia virus (EIAV)attenuated vaccine enhance immunogenicity, both for DNA immunization alone and as a combined DNA prime-vaccinia boost immunization. An RV144 clinical trial has demonstrated that an envelope protein boost may provide some degree of protection against HIV-1 infection.

Regulation of metabolic flux in Lactobacillus casei for lactic acid production by overexpressed ldhL gene with two-stage oxygen supply strategy.

This study describes a novel strategy to regulate the metabolic flux for lactic acid production in Lactobacillus casei. The ldhL gene encoding L-lactate dehydrogenase (L-LDH) was overexpressed in L. casei, and a two-stage oxygen supply strategy (TOS) that maintained a medium oxygen supply level during the early fermentation phase, and a low oxygen supply level in the later phase was carried out.

Improve carbon metabolic flux in Saccharomyces cerevisiae at high temperature by overexpressed TSL1 gene.

This study describes a novel strategy to improve the glycolysis flux of Saccharomyces cerevisiae at high temperature. The TSL1 gene-encoding regulatory subunit of the trehalose synthase complex was overexpressed in S. cerevisiae Z-06, which increased levels of trehalose synthase activity in extracts, enhanced stress tolerance and glucose consuming rate of the yeast cells.

The effect of temperature on L-lactic acid production and metabolite distribution of Lactobacillus casei.

The effect of temperature on the growth and L-lactic acid production of Lactobacillus casei G-03 was investigated in a 7-L bioreactor. It was found that the maximum specific growth rate (0.27 hr⁻¹) and L-lactic acid concentration (160.

Improvement of polygalacturonase production at high temperature by mixed culture of Aspergillus niger and Saccharomyces cerevisiae.

Catabolic repression in the synthesis of inducible enzymes by glucose, fructose, and intermediates of the glycolytic cycle has been observed in many microorganisms. In order to enhance the polygalacturonase (PG) production of Aspergillus niger GJ-2, Saccharomyces cerevisiae J-1 was inoculated to the medium at 12h of culture, which resulted in a significant improvement of PG production. It was also found that maximum PG activity of 512.

Improvement of L-lactic acid production by osmotic-tolerant mutant of Lactobacillus casei at high temperature.

L-Lactic acid production by Lactobacillus casei was used as a model to study the mechanism of substrate inhibition and the strategy for enhancing L-lactic acid production. It was found that the concentration of cell growth and L-lactate decreased with the increase of glucose concentration and fermentation temperature. To enhance the osmotic stress resistance of the strain at high temperature, a mutant G-03 was screened and selected with 360 g/L glucose at 45°C as the selective criterion.

Enhancement of L-lactic acid production in Lactobacillus casei from Jerusalem artichoke tubers by kinetic optimization and citrate metabolism.

Efficient L-lactic acid production from Jerusalem artichoke tubers by Lactobacillus casei G-02 using simultaneous saccharification and fermentation (SSF) in fed-batch culture is demonstrated. The kinetic analysis in the SSF signified that the inulinase activity was subjected to product inhibition, while the fermentation activity of G-02 was subjected to substrate inhibition. It was also found that the intracellularly NOX activity was enhanced by the citrate metabolism, which increased the carbon flux of Embden-Meyerhof-Parnas (EMP) pathway dramatically, and resulted more ATP production.

Improvement of L-lactic acid production from Jerusalem artichoke tubers by mixed culture of Aspergillus niger and Lactobacillus sp.

Aspergillus niger SL-09 and Lactobacillus sp. G-02 were used as a mixed culture in a 7-l fermentor to directly form L-lactic acid from Jerusalem artichoke tubers. The synthesis of inulinase and invertase from A.

Improved production of an enzyme that hydrolyses raw yam starch by Penicillium sp. S-22 using fed-batch fermentation.

A newly isolated strain, Penicillium sp. S-22, was used to produce an enzyme that hydrolyses raw yam starch [raw yam starch digesting enzyme (RYSDE)]. The enzyme activity and overall enzyme productivity were respectively 16 U/ml and 0.