Identification and characterization of a psychrophilic yeast strain newly isolated from the fermentative starter (Loog-pang) of a traditional drink in Thailand.

One psychrophilic yeast strain, that grew well in a cold environment such as in a refrigerator, was isolated from the yeast starter (Loog-pang) of a traditional alcohol drink in Thailand. The isolated strain OPU-FC11 was identified as Cryptococcus diffluens by the assay for 26S ribosomal DNA and the test for carbon source assimilation. OPU-FC11 showed a good amount of growth at 4 degrees 0 at which a commonly found yeast like Saccharomyces cerevisiae did not grow, and produced cold-adapted enzymes that showed a relatively high activity at lower temperatures.

Purification, characterization, and overexpression of thermophilic pectate lyase of Bacillus sp. RN1 isolated from a hot spring in Thailand.

A thermophilic pectate lyase, Pel SWU, was isolated from a culture filtrate of Bacillus sp. RN1 isolated from a hot spring in Ranong Province, Thailand. The enzyme was purified to homogeneity using cation-exchange and hydrophobic column chromatographies.

Enzymatic synthesis of hydroxycinnamic acid glycerol esters using type A feruloyl esterase from Aspergillus niger.

We found that hydroxycinnamic acid (HA) glycerol esters such as 1-sinapoyl glycerol and 1-p-coumaroyl glycerol can be synthesized through a direct esterification reaction using a type A feruloyl esterase from Aspergillus niger. The water solubilities of HA glycerol esters were higher than those of the original chemicals. HA glycerol esters absorbed ultraviolet light and scavenged 1,1-diphenyl-2-picrylhydrazyl radicals.

Characterization of Fusarium oxysporum beta-1,6-galactanase, an enzyme that hydrolyzes larch wood arabinogalactan.

A type II arabinogalactan-degrading enzyme (FoGal1) was purified from Fusarium oxysporum 12S, and the corresponding cDNA was isolated. FoGal1 had high similarity to enzymes of glycoside hydrolase family 5. Treatment of larch wood arabinogalactan with the recombinant enzyme indicated that FoGal1 is a beta-1,6-galactanase that preferentially debranches beta-1,6-galactobiose from the substrate.

Expression of Aspergillus oryzae phytase gene in Aspergillus oryzae RIB40 niaD(-).

Aspergillus oryzae RIB40 niaD(-) was transformed using a plasmid constructed with the A. oryzae phytase gene and pNAN8142 vector. The culture broth of the transformant, which was grown in a medium containing starch as a carbon source and polyvinylpyrrolidone showed phytase activity of a maximum of 2.

Growth characteristics of fusants by protoplast fusion between the thermotolerant yeast, Kluyveromyces marxianus, and the starch-assimilating yeast, Schwanniomyces occidentalis.

Intergeneric fusants were obtained by protoplast fusion between the thermotolerant yeast, Kluyveromyces marxianus, and the starch-assimilating yeast, Schwanniomyces occidentalis. Two thermotolerant fusants growing at 40 degrees C were screened on the medium containing soluble starch. These fusants showed weak growth in a soluble starch medium and the production of a little amylase.

Esterification of ferulic acid with polyols using a ferulic acid esterase from Aspergillus niger.

Commercially available enzyme preparations were screened for enzymes that have a high ability to catalyze direct ester-synthesis of ferulic acid with glycerol. Only a preparation, Pectinase PL "Amano" produced by Aspergillus niger, feruloylated glycerol under the experimental conditions. The enzyme responsible for the esterification was purified and characterized.

Functional analysis of unique class II insertion sequence IS1071.

Various xenobiotic-degrading genes on many catabolic plasmids are often flanked by two copies of an insertion sequence, IS1071. This 3.2-kb IS element has long (110-bp) terminal inverted repeats (IRs) and a transposase gene that are phylogenetically related to those of the class II transposons.

Characteristics of wines made by Saccharomyces mutants which produce a polygalacturonase under wine-making conditions.

Wines by yeast mutants producing polygalacturonase in high glucose concentration, from Saccharomyces wine-making strains, had higher filterability and more concentrated anthocyanin contents than that of their parent strains. These results suggest that the clarification process was improved at a lower cost by the low viscosity and that high-quality wines result from the increase in the anthocyanin contents.

Endo-polygalacturonase in Saccharomyces wine yeasts: effect of carbon source on enzyme production.

Eight wine yeast strains of Saccharomyces sp. were tested for polygalacturonase (PGase) activity, after cultivation on various carbon sources. No strain showed any activity when grown on glucose, while five strains produced PGase in the presence of galactose and polygalacturonate.

Transglycosylation catalyzed by a Penicillium chrysogenum exo-1,5-alpha-L-arabinanase.

Penicillium chrysogenum exo-arabinanase (Abnx), which releases arabinobiose from the nonreducing terminus of alpha-1,5-L-arabinan, was found to possess trans-arabinobiosylation activity on various acceptors, such as aliphatic alcohols, sugars, and sugar alcohols. Abnx was found to prefer primary hydroxyl groups in polyhydric alcohols as acceptors over primary hydroxyl groups in monohydric alcohols. Among the 21 different compounds tested, glycerol was the best acceptor for the enzyme.

Reactivity of asparagine residue at the active site of the D105N mutant of fluoroacetate dehalogenase from Moraxella sp. B.

Fluoroacetate dehalogenase from Moraxella sp. B (FAc-DEX) catalyzes cleavage of the carbon-fluorine bond of fluoroacetate, whose dissociation energy is among the highest found in natural products. Asp105 functions as the catalytic nucleophile that attacks the alpha-carbon atom of the substrate to displace the fluorine atom.

Molecular characterization of a Penicillium chrysogenum exo-1,5-alpha-L-arabinanase that is structurally distinct from other arabinan-degrading enzymes.

The nucleotide sequence of the abnx cDNA gene, which encodes an exo-arabinanase (Abnx) of Penicillium chrysogenum 31B, was determined. Abnx was found to be structurally distinct from known arabinan-degrading enzymes based on its amino acid sequence and a hydrophobic cluster analysis. The protein in the protein database with the highest similarity to Abnx was the Neurospora crassa conserved hypothetical protein.

Structure of haloacetate-catabolic IncP-1beta plasmid pUO1 and genetic mobility of its residing haloacetate-catabolic transposon.

The self-transmissible plasmid pUO1 from Delftia acidovorans strain B carries two haloacetate-catabolic transposons, TnHad1 and TnHad2, and the mer genes for resistance to mercury. The complete 67,066-bp sequence of pUO1 revealed that the mer genes were also carried by two Tn402/Tn5053-like transposons, Tn4671 and Tn4672, and that the pUO1 backbone regions shared 99% identity to those of the archetype IncP-1beta plasmid R751. Comparison of pUO1 with three other IncP-1beta plasmids illustrated the importance of transposon insertion in the diversity and evolution of this group of plasmids.

Catalysis-linked inactivation of fluoroacetate dehalogenase by ammonia: a novel approach to probe the active-site environment.

Fluoroacetate dehalogenase from Moraxella sp. B (FAc-DEX) catalyzes the hydrolytic dehalogenation of fluoroacetate and other haloacetates. Asp(105) of the enzyme acts as a nucleophile to attack the alpha-carbon of haloacetate to form an ester intermediate, which is subsequently hydrolyzed by a water molecule activated by His(272) [Liu, J.

Characterization of a class II defective transposon carrying two haloacetate dehalogenase genes from Delftia acidovorans plasmid pUO1.

The two haloacetate dehalogenase genes, dehH1 and dehH2, on the 65-kb plasmid pUO1 from Delftia acidovorans strain B were found to be located on transposable elements. The dehH2 gene was carried on an 8.9-kb class I composite transposon (TnHad1) that was flanked by two directly repeated copies of IS1071, IS1071L and IS1071R.

Cloning of a protopectinase gene of Trichosporon penicillatum and its expression in Saccharomyces cerevisiae.

A protopectinase (PPase)-encoding gene, PSE3, from Trichosporon penicillatum was cloned by colony hybridization using two oligonucleotide probes synthesized from the N-terminal amino acid sequences of native PPase SE1 and one peptide from a lysyl endopeptidase digest. Nucleotide sequencing revealed that PSE3 contains an ORF encoding a 367 amino acid protein. Mature PPase SE3 is composed of 340 amino acids and the N-terminus of the ORF appeared to correspond to a signal peptide and a propeptide processed by a KEX2-like proteinase.