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This research aimed to study lead accumulation and the type of rhizobacteria associated with maize grown in the lead-contaminated area of Klity village, Kanchanaburi Province, Thailand. The results showed that lead concentrations in different tissues were roots > shoots > grains. The highest lead concentration was recorded on day 120 (54.31, 110.67 and 4.79 mg⋅kg-1 in shoots, roots, and grains, respectively). The lowest lead concentration was recorded on day 40 (27.80 and 71.90 mg⋅kg-1 in shoots and roots, respectively) with no detectable lead in the grain. Results indicate that lead concentration in grains on day 120 of the experiment exceeded the European Union Standard (0.2 mg⋅kg-1), which might not be safe for human consumption but did not exceed the standard as animal feed (30 mg⋅kg-1). This research found four species of bacteria that could grow in soil at a lead concentration exceeding 3,600 mg⋅kg-1, namely Bacillus sp. B26, Pseudomonas sp. S169, Pseudomonas putida strain RW10S2, and Bacillus subtilis strain SM10. [ABSTRACT FROM AUTHOR]

The article reports on the molecular cloning of cDNA for trehalase from the European honeybee, Apis mellifera and its heterologous expression in Pichia pastoris. The mature enzyme comprised of 591 amino acids. The six peptide sequences analyzed were found in the deduced amino acid sequence, which exhibited high identity with trehalases which belong to the glycoside hydrolase family.

The article discusses a study which describes the molecular cloning of chromosomal deoxyribonucleic acids (cDNA) encoding three alpha-glucosidases including HBGases I, II and III from European honeybees, Apis mellifera, which are expressed in Pichia pastoris. It is showed that the gene of HBGase I composed of eight exons and seven introns. The HBGase II was not divided by intron and the gene of HBGase III was confirmed to be made up of nine exons and eight introns.

The article discusses the purification and characterization of a-Glucosidase (JHGase I) from a Japanese subspecies of eastern honeybee (Apis cerena japonica). The JHGase I was isolated from component 1 to undergo further purification using CM-Tojopearl 650M and Sepharel S-100. JHGase I showed unusual kinetic features: the negative cooperative behavior on the intrinsic reaction and positive cooperative on turanose. In addition, JHGase I is a member of a-amylase family enzymes.

Focuses on localization of α-glucosidases I,II and III in organs of European honeybees, Apis mellifera L. and the origin of α-glucosidase in honey. Preparation of specific antisera against the α-glucosidases to examine the localization of α-glucosidases in the organs of honeybees; Confirmation for the fist time that α-glucosidase I was present in ventriculus and haemolymph; Suggestion that honey may be finally made up through the process whereby sucrose in nectar is hydrolyzed by secreted α-glucosidase III.

cDNA encoding the bound type trehalase of the European honeybee was cloned. The cDNA (3,001 bp) contained the long 5' untranslated region (UTR) of 869 bp, and the 3' UTR of 251 bp including a poly(A) tail, and the open reading frame of 1,881 bp consisting of 626 amino acid residues. The Mr of the mature enzyme comprised of 591 amino acids, excluded a signal sequence of 35 amino acid residues, was 69,177. Six peptide sequences analyzed were all found in the deduced amino acid sequence. The amino acid sequence exhibited high identity with trehalases belonging to glycoside hydrolase family 37. A putative transmembrane region similar to trehalase-2 of the silkworm was found in the C-terminal amino acid sequence. Recombinant enzyme of the trehalase was expressed in the methylotrophic yeast Pichia pastoris as host, and displayed properties identical to those of the native enzyme except for higher sugar chain contents. This is the first report of heterologous expression of insect trehalase.

cDNAs encoding three alpha-glucosidases (HBGases I, II, and III) from European honeybees, Apis mellifera, were cloned and sequenced, two of which were expressed in Pichia pastoris. The cDNAs for HBGases I, II, and III were 1,986, 1,910, and 1,915 bp in length, and included ORFs of 1,767, 1,743, and 1,704 bp encoding polypeptides comprised of 588, 580, and 567 amino acid residues, respectively. The deduced proteins of HBGases I, II, and III contained 18, 14, and 8 putative N-linked glycosylation sites, respectively, but at least 2 sites in HBGase II were unmodified by N-linked oligosaccharide. In spite of remarkable differences in the substrate specificities of the three HBGases, high homologies (38-44% identity) were found in the deduced amino acid sequences. In addition, three genomic DNAs, of 13,325, 2,759, and 27,643 bp, encoding HBGases I, II, and III, respectively, were isolated from honeybees, and the sequences were analyzed. The gene of HBGase I was found to be composed of 8 exons and 7 introns. The gene of HBGase II was not divided by intron. The gene of HBGase III was confirmed to be made up of 9 exons and 8 introns, and to be located in the region upstream the gene of HBGase I.

Three kinds of alpha-glucosidases, I, II, and III, were purified from European honeybees, Apis mellifera L. In addition, an alpha-glucosidase was also purified from honey. Some properties, including the substrate specificity of honey alpha-glucosidase, were almost the same as those of alpha-glucosidase III. Specific antisera against the alpha-glucosidases were prepared to examine the localization of alpha-glucosidases in the organs of honeybees. It was immunologically confirmed for the first time that alpha-glucosidase I was present in ventriculus, and alpha-glucosidase II, in ventriculus and haemolymph. alpha-Glucosidase III, which became apparent to be honey alpha-glucosidase, was present in the hypopharyngeal gland, from which the enzyme may be secreted into nectar gathered by honeybees. Honey may be finally made up through the process whereby sucrose in nectar, in which glucose and fructose also are naturally contained, is hydrolyzed by secreted alpha-glucosidase III.