Lactococcus lactis subspecies lactis (L. lactis ssp. lactis) and Lactococcus lactis subspecies cremoris (L. lactis ssp. cremoris) were investigated in respect to their response to acid, bile-salt and freezing stresses. First, the sublethal and lethal levels of each stress were determined for both subspecies. For acid stress, the levels were pH 4.5 and 2.5, respectively, for L. lactis ssp. lacti...

Interest in the production of L-(+)-lactic acid is presently growing in relation to its applications in the synthesis of biodegradable polymer materials. With the aim of obtaining efficient production and high productivity, we introduced the bovine L-lactate dehydrogenase gene (LDH) into a wild-type Kluyveromyces lactis yeast strain. The observed lactic acid production was not satisfactory due ...

The GAL4 protein of Saccharomyces cerevisiae and the LAC9 protein of Kluyveromyces lactis are transcription activator proteins with similar structure and function. Greatest similarity occurs in the C region near the carboxy terminus, where 16 of 18 amino acids are identical. The function of the C region is unclear. Here we show that the structural similarity is reflected in functional similarit...

We have constructed strains of Saccharomyces cerevisiae that grow on lactose (Lac+). S. cerevisiae strain YNN27, which, like all S. cerevisiae, is unable to grow on lactose, was transformed with pKR1B-LAC4-1. This plasmid has a selectable marker gene conferring resistance to the antibiotic G418 and carries a 13-kilobase region of the Kluyveromyces lactis genome including LAC4, a beta-galactosid...

The KlICL1 gene, encoding isocitrate lyase in Kluyveromyces lactis, is essential for ethanol utilization. Deletion analyses identified two functional promoter elements, CSRE-A and CSRE-B. Transcription is activated on ethanol, but not on glucose, glycerol or lactate. Expression depends on the KlCat8p transcription factor and KlSip4p binds to the promoter elements. Glycerol diminishes KlICL1 exp...

A specialized nucleosome is a component of all eukaryotic kinetochores. The core of this nucleosome contains a centromere-specific histone, CENP-A (the Cse4 gene product in budding yeast), instead of the usual H3. Assembly of a centromeric nucleosome depends on a specific chaperone, called Scm3 in yeast and HJURP in higher eukaryotes. We describe here the structure of a complex formed by an N-t...

Efficient centromeric and multicopy vectors have been constructed for the yeast Kluyveromyces marxianus using homologous ARS and centromere sequences. A homologous promoter of a purine-cytosine permease gene called PCPL3 has been cloned, using an expression system based on GUS. Its strength has been estimated in K. marxianus by putting the homologous beta-glucosidase gene under its control. Thi...

One-step sulfuric acid saccharification of the red alga Pterocladiella capillacea was optimized, and various detoxification methods (neutralization, overliming, and electrodialysis) of the acid hydrolysate were evaluated for fermentation with the thermotolerant yeast Kluyveromyces marxianus. A proximate composition analysis indicated that P. capillacea was rich in carbohydrates. A significant g...