Lian Hua Luo

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In a previous study, we showed that 1,3-propanediol (1,3-PD) was still produced from glycerol by the Klebsiella pneumoniae mutant strain defective in 1,3-PD oxidoreductase (DhaT), although the production level was lower compared to the parent strain. As a potential candidate for another putative 1,3-PD oxidoreductase, we identified and characterized a(More)
In the present study, mutant strain of Klebsiella pneumoniae with deletion of the crr gene encoding EIIA(Glc) (a component of the glucose-specific phosphoenolpyruvate-dependent transferase system [PTS]) was prepared. This eliminated the ability of the strain to mediate carbon catabolite repression (CCR). Production of 1,3-propanediol (1,3-PD) from glycerol(More)
A mutant strain of Klebsiella pneumoniae, termed GEM167, was obtained by γ irradiation, in which glycerol metabolism was dramatically affected on exposure to γ rays. Levels of metabolites of the glycerol reductive pathway, 1,3-propanediol (1,3-PD) and 3-hydroxypropionic acid (3-HP), were decreased in the GEM167 strain compared to a control strain, whereas(More)
To investigate the effect of cellular fatty acids composition on ethanol tolerance in Escherichia coli, we overexpressed either des, encoding fatty acid desaturase from Bacillus subtilis, or fabA, encoding β-hydroxydecanoyl thio-ester dehydrase from E. coli, or both genes together, into E. coli. Recombinant E. coli harboring fabA had elevated tolerance(More)
Previously, we constructed a glycerol oxidative pathway-deficient mutant strain of Klebsiella pneumoniae by inactivation of glycerol dehydrogenase (dhaD) to eliminate by-product synthesis during production of 1,3-propanediol (1,3-PD) from glycerol. Although by-product formation was successfully blocked in the resultant strain, the yield of 1,3-PD was not(More)
To improve production of ethanol from glycerol, the methylotrophic yeast Hansenula polymorpha was engineered to express the pdc and adhB genes encoding pyruvate decarboxylase and aldehyde dehydrogenase II from Zymomonas mobilis, respectively, under the control of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) promoter. The ethanol yield was 3.3-fold(More)
Currently, 1,3-propanediol (1,3-PD) is an important chemical widely used in polymer production, but its availability is being restricted owing to its expensive chemical synthesis. A methylotrophic yeast Hansenula polymorpha was engineered by expression of dhaB1, dhaB2, dhaB3, dhaB(RA1) and dhaB(RA2) encoding glycerol dehydratase complex and dhaT encoding(More)
Although the de novo biosynthetic mechanism of 3-hydroxypropionic acid (3-HP) in glycerol-fermenting microorganisms is still unclear, the propanediol utilization protein (PduP) of Lactobacillus species has been suggested to be a key enzyme in this regard. To verify this hypothesis, a pduP gene from Lactobacillus reuteri was cloned and expressed, and the(More)
Klebsiella pneumoniae produces 3-hydroxypropionic acid (3-HP) from glycerol with oxidation of 3-hydroxypropionaldehyde (3-HPA) to 3-HP in a reaction catalyzed by aldehyde dehydrogenase (ALDH). In the present study, two putative ALDHs of K. pneumoniae, YneI and YdcW were identified and characterized. Recombinant YneI was specifically active on 3-HPA and(More)
To discover an active skin depigmenting agent, we isolated a novel inhibitor of melanin biosynthesis from the methanol extract of Erigeron breviscapus using a bioactivity-guided fractionation and identified it as (2Z,8Z)-matricaria acid methyl ester by means of spectroscopic analysis. The compound showed strong whitening activity in melan-a cell. Compared(More)