Enhancement of monascus pigment production by the culture of Monascus sp. J101 at low temperature

In general, high broth viscosity is a key factor to be considered in a submerged fermentation of filamentous fungi. High broth viscosity was also observed in a batch fermentation of Monascus sp. J101 at 30 degrees C. In a batch culture at 30 degrees C, most cell growth was accomplished within 48 h, which induced highly entangled clumps. The resultant high viscosity induced heterogeneity inside the fermentor, poor oxygen transfer, and low pigment yield. However, these problems could be overcome by reducing fungal growth rate through culture at low temperature (25 degrees C). Cell growth was moderate and continued for 120 h, and low viscosity was maintained. The DO levels remained at 50% or higher with good mixing. As a result, the pigment yield at 25 degrees C was 10 times greater than at 30 degrees C.     

Translation elongation factor 1-α gene from <Emphasis Type="Italic">Pichia pastoris</Emphasis>: molecular cloning,sequence, and use of its promoter

The gene encoding translation elongation factor 1-α from the yeast Pichia pastoris was cloned. The gene revealed an open reading frame of 1,380 bp with the potential to encode a polypeptide of 459 amino acids with a calculated mass of 50.1 kDa. The potential of the promoter (P _TEF1 ) in P. pastoris was investigated with comparison to the glyceraldehyde-3-phosphate dehydrogenase promoter (P _GAP ) by using a bacterial lipase gene as a reporter gene. P _TEF1 demonstrated a tighter growth-associated expression mode, improved functioning in the presence of high glucose concentrations, and promoter activities that yielded recombinant protein at levels similar to or in one case greater than P _GAP . The sequence of the gene was deposited in GenBank under accession no. EF014948.