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A bifunctional alcohol/acetaldehyde dehydrogenase (AdhE) gene (adhE) was cloned from Leuconostoc mesenteroides C7 (LMC7), which is the dominant lactic acid bacterium produced during heterofermentation of kimchi. The nucleotide sequence of the DNA fragment containing putative adhE, which is 2685 bp long and encodes an 886 amino acid polypeptide, exhibits 99% homology with Leu. mesenteroides sp. cremoris. The deduced AdhE comprises two conserved domains: alcohol dehydrogenase (Adh) and acetaldehyde dehydrogenase (Aldh). Moreover, two NAD-binding sites were observed, based on the presence of the GXGXXG motif. A pADHE containing the adhE gene expressed AdhE at the translational level in Escherichia coli BL21, which was at a higher level than in E. coli DH5alpha and E. coli JM109. The AdhE of LMC7 showed Adh and Aldh activities that, when expressed in E. coli. BL21, were 7.5 and 5.7 U mg(-1) , respectively.

A DNA fragment, which complemented the growth of E. coli both on M9 medium containing raffinose and on LB medium containing ampicillin, IPTG and 5-bromo-4-chloro-3-indoxyl-α-d-galactoside, was isolated from the genomic library of Bifidobacterium longum SJ32, which had been digested with EcoRI. In the cloned DNA fragment, a gene encoding a sucrose phosphorylase (splP) and a partially cloned putative sucrose regulator gene (splR) were identified using the deletion analysis and sequence analysis. A 56 kDa protein was synthesized in E. coli and partially purified by DEAE-ion exchange chromatography. The partially purified enzyme did not react with melibiose, melezitoze and raffinose but did with sucrose. It had transglucosylation activity in addition to hydrolytic activity.

Whole cells, cytoplasms and peptidoglycans of ten different lactic acid bacteria (LAB) were tested for in vitro cytotoxicity on diverse cancer cell lines using the 3H-thymidine incorporation assay. The peptidoglycans and cytoplasm fractions, as well as heat-killed whole cells of LAB, had significant antiproliferative activities against several cancer cell lines. In particular, the cytoplasm fractions exhibited marked direct antiproliferative activities against colon and gastric cancer cell lines, whereas the peptidoglycans retarded growth of colon and bladder cancer cell lines. The cytoplasm fractions of Bifidobacterium longum and Lactococcus lactis ssp. lactis inhibited proliferation of two cancer cell lines by 50% at 33 and 23 μg ml−1 for SNUC2A (a human colon adenocarcinoma cell line) and 17 and 11 μg ml−1 for SNU-1 (a human gastric cancer cell line), respectively.

Zanthoxylum piperitum (prickly ash) was grown as a suspension culture in Schenk and Hildebrandt medium supplemented with 50 g sucrose l−1 and 0.5 mg 2,4-dichlorophenoxyacetic acid l−1 for 21 days with elicitation by pectin added at day 15. Volatile compounds were extracted from the culture and 3-hydroxy-2-butanone was identified by GC-MS as the most abundant compound, followed by γ-butyrolactone and 2,3-butanedione. 2,3-Butanedione, ethyl 3-methylbutyrate, and ethyl 2-methylpropanoate were identified as the most intense aroma-active compounds and represented the characteristic aroma of the culture.

High paclitaxel production (26 mg l−1) was achieved through the intermittent feeding of 3, 1, and 2% (w/v) sucrose at days 0, 7, and 21, respectively, to a suspension culture of Taxus chinensis cells. Intermittent feedings of 1 and 2% (w/v) maltose at days 7 and 21, respectively, to the culture increased the paclitaxel production up to 67 mg l−1.

The gene encoding β-galactosidase of Lactococcus lactis ssp. lactis ATCC7962 was cloned and its nucleotide sequence was determined. The β-galactosidase of L. lactis was expressed in Escherichia coli and transformants containing this gene fragment appeared as blue colonies on LB plates containing X-gal. The β-galactosidase activity of E. coli transformant was thirty times higher than that of L. lactis. The gene for the 115 kDa β-galactosidase has a 2991-bp open reading frame preceded by a putative ribosome binding site. The deduced amino acid sequence show a high degree of homology to the β-galactosidase of E. coli, and the putative active site residues are conserved (Glu-429 and Tyr-475)

Indole when added at 20 mM to shake flask cultures of Polygonum tinctorium cells on 16th day increased indirubin production from 41 mg/l to 126 mg/l. Use of KNO3 depleted media stimulated indirubin formation up to 88% and 26% in shake flasks and air-lift bioreactors, respectively.

The optimum concentration of chitosan to menthol production by Mentha piperita cells cultured in shake flasks was 200 mg/l, which gave 166 mg menthol/l after 12 days. Chitosan elicitation may activate the conversion of pulegone to menthol.

The gene encoding phosphoketolase, which is 2749 bp long and contains 814 amino acid polypeptides with a total molecular mass of 91.9 kDa, was cloned from Leuconostoc mesenteroides C7 (LMC7) and expressed in Escherichia coli. It exhibited a homology of58% with phosphoketolases from other lactic acid bacteria. The phosphoketolase of LMC7 belongs to the xylulose 5-phosphate (X5P)/fructose 6-phosphate (F6P) phosphoketolase (Xfp) family, which is an enzyme with dual specificity for X5P and F6P. The members of this family contain typical thiamin pyrophosphate (TPP) binding sites as reported for other TPP-dependent enzymes, and several highly conserved regions as signature patterns for phosphoketolases. The plasmid pGPK containing the Xfp gene (xfp) exhibits phosphoketolase activity in E. coli. The specific activities of the enzyme from E. coli BL21 and E. coli EC101 harboring xfp were 0.28 and 0.14 units/mg, respectively. They both exhibited a 1.5-fold increase in the production of acetic acid from acetyl phosphate compared with their corresponding original strain.

A DNA fragment, which complemented the growth of E. coli both on M9 medium containing raffinose and on LB medium containing ampicillin, IPTG and 5-bromo-4-chloro-3-indoxyl-alpha-D-galactoside, was isolated from the genomic library of Bifidobacterium longum SJ32, which had been digested with EcoRI. In the cloned DNA fragment, a gene encoding a sucrose phosphorylase (splP) and a partially cloned putative sucrose regulator gene (splR) were identified using the deletion analysis and sequence analysis. A 56 kDa protein was synthesized in E. coli and partially purified by DEAE-ion exchange chromatography. The partially purified enzyme did not react with melibiose, melezitoze and raffinose but did with sucrose. It had transglucosylation activity in addition to hydrolytic activity.

The gene encoding phosphoketolase, which is 2749 bp long and contains 814 amino acid polypeptides with a total molecular mass of 91.9 kDa, was cloned from Leuconostoc mesenteroides C7 (LMC7) and expressed in Escherichia coli. It exhibited a homology of >58% with phosphoketolases from other lactic acid bacteria. The phosphoketolase of LMC7 belongs to the xylulose 5-phosphate (X5P)/fructose 6-phosphate (F6P) phosphoketolase (Xfp) family, which is an enzyme with dual specificity for X5P and F6P. The members of this family contain typical thiamin pyrophosphate (TPP) binding sites as reported for other TPP-dependent enzymes, and several highly conserved regions as signature patterns for phosphoketolases. The plasmid pGPK containing the Xfp gene (xfp) exhibits phosphoketolase activity in E. coli. The specific activities of the enzyme from E. coli BL21 and E. coli EC101 harboring xfp were 0.28 and 0.14 units/mg, respectively. They both exhibited a 1.5-fold increase in the production of acetic acid from acetyl phosphate compared with their corresponding original strain.