Search

The article discusses the findings of a study which determined the role of genes in oxidative fermentation of D-sorbitol in Gluconobacter frateurii bacteria. The researchers described the oxidizing characteristic of the Gluconobacter in producing L-sorbose, 2- and 5-keto-D-gluconates, and the Miglitol drug. The experiment confirmed the identification and characterization of D-sorbitol dehydrogenase genes including sldR, xdhA, and perA.

The article presents a study that attempts to identify the genes essential for growth at high temperature by transposon (Tn10) mutagenesis to elucidate the mechanism underlying the thermotolerance of mesophilic strains. It states that Acetobacter tropicalis SKU1100 is a thermotolerant acetic acid bacterium that dwells even at high temperatures. Results have further supported the partial overlap between the genes required for acetic acid resistance and those needed for thermotolerance.

The article focuses on the production of 4-keto-D-arabonate (4KAB) by Gluconacetobacter liquefaciens strains. It states that the strains accumulated 2,5-diketo-d-gluconate (25DKA) and oxidized D-gluconate, D-glucose, and 2-keto-D-gluconate (2KGA). It says that after the accumulation, 25DKA was converted into 4KAB and 4KAB remained stable in Gluconacetobacter liquefaciens. Moreover, a study of M. Ameyama and K. Kondo on carbohydrate metabolism of acetic acid bacteria assumed the 4KAB occurrence.

The article presents a study regarding the productiuon of 3-dehydroshikimate (DSA) from quinate by immobilixing the membrane fraction of the acetic acid bacteria Gluconobacter oxydans IFO 3244. The study used several methods to realize and examine the immobilization process including encapsulation, ionic binding, and physical adsorption. Results show a conversion rate of almost 100% from quinate to 3-dehydroshikimate.

The article presents a study concerning acetic acid fermentation of Acetobacter pasteurianus. The study involves the examination of the relationship between pellicle polysaccharide formation and acetic acid resistance. It shows that acetic acid resistance ability pellicle formation is primarily related to pellicle formation, thus is essential to acetic acid fermentation in A. pasteurianus strains.

The article presents a study that focuses on the purification and characterization of the membrane-bound 3-dehydroshikimate dehydratase (mDSD) and enzyme solubilization from the membrane fraction of gluconobacter oxydans IFO 3244. The results revealed that the mDSD in the membrane fraction suggests the mDSD's significance of aromatization, solubilized and purified to high homogeneity. It says that dehydroshikimate (DSA) was confirmed as a direct precursor of phenylcyclohexylamine (PCA).

The article discusses membrane-bound glucono-δ-lactonase (MGL) properties, solubility, and enzyme purification. It presents the process wherein MGL is purified from Gluconobacter oxydans. It also discusses that the involved acetic acid bacteria and aerobic bacteria in the oxidative fermentation contains a well-developed periplasmic oxydase system which yields bioenergy formation.

Chlorogenate hydrolase (EC 3.1.1.42, CHase) was highly induced in mycelia of Aspergillus sojae AKU 3312 grown in Czapek medium containing either instant coffee powder or coffee pulp as inducer. No CHase formation was observed in the mycelia when cultivated without the inducer. CHase was purified readily from CHase-induced mycelia to high homogeneity, and the purified CHase revealed the molecular weight of 180,000 consisting of two identical subunits of 88 kDa. Equimolar quinate (QA) and caffeate (CA) were confirmed on hydrolysis of chlorogenate (CGA). The purified CHase was only useful for a laboratory scale hydrolysis of CGA. For practical QA and CA production using scaled up hydrolysis of vegetable extracts of natural CGA resources, the enzyme activity of purified CHase decreased and denatured irreversibly. Preparation of coffee pulp koji and its application to QA and CA production were proposed instead of purified CHase. When coffee pulp koji was heated at 60°C for 30 min, CHase survived without any appreciable loss of enzyme activity while vegetative mycelial growth and spore germination were terminated. The heated coffee pulp koji thus prepared was effective itself as stable immobilized catalyst of CHase for QA and CA production from vegetable CGA resources such as coffee powders, coffee pulp, and others. [ABSTRACT FROM AUTHOR]

The article studies tightly-bound quinone functions in the ubiquinone reaction sites of the quinoprotein alcohol dehydrogenase (ADH) of the Gluconobacter suboxydans bacterium in acetic acid. It includes an in-depth analysis of the solubilization and purification of ADH with dodecyl maltoside, as well as a discussion on the issues' implications for biological chemistry.

The article presents a study which examines the purification and properties of dihydroxyacetone (DHA) reductases in gluconobacter suboxydans grown in gycerol. It states that two DHA reductases were detected in the same cytoplasm gluconobacter suboxydans. It notes that NADH-dependent appears inducible and labile in nature while the NADPH-dependent appears constitutive and stable. It also notes that the two DHARS were specific only to DHA reduction to glycerol.

The article reports on a study on the novel 3-dehydroquinate dehydrase (DQD) catalyzing extracellular formation of 3-dehydroshikimate by oxidative fermentation of Gluconobacter oxydans IFO 3244. The study showed that the same apparent molecular weights and same catalytic properties, but they were distinct from each other in subunit molecular mass.

The article discusses a study which investigated the energy metabolism and respiratory chain of Asaia bogorensis. A. bogorensis is a unique acetic acid bacterium with unusual properties including scanty acetic acid production and rapid growth. The found that A. bogorensis lacks quinoprotein alcohol dehydrogenase, but has sugar and sugar alcohol-oxidizing enzymes specific to the respiratory chain of Gluconobacter.

The article reports on results of a study of physiological roles of two membrane-bound dehydrogenases responsible for d-sorbitol oxidation in Gluconobacter frateurii. A description of the study design and method is presented. The study concluded that pyroloquinoline quinone-dependent glycerol dehydrogenase (PQQ-GLDH) connects efficiently to cytochrome bo3 terminal oxidase.

The article examines the purification and properties of NADP-dependent shikimate dehydrogenase (SKDH) from Gluconobacter oxydans IFO 3244 and its application to enzymatic shikimate production. It showed a single protein band on native-polyacrylamide gel electrophoresis accompanying activity when SKDH was purified from Gluconobacter oxydans IFO 3244. It required NADP exclusively and catalyzed only the shuttle reaction between shikimate and 3-dehydroshikimate.

The article discusses the study about the conversion of capsular polysaccharide (CPS) to extracellular polysaccharide (EPS) by galE deletion in acetobacter tropicalis. A clone of the galE gene from Acetobacter tropicalis was performed. Results show that the cloned gene does not produce CPS, but secreted an EPS, which is purified and having a unique characteristic from the original CPS.

The article discusses the results of a study which examined membrane-bound NAD(P)-independent formaldehyde-oxidizing enzyme from Acetobacter sp. SKU 14. The enzyme was solubilized from the membrane fraction of glycerol-grown cells and was purified to homogeneity through column chromatographies. The purified enzyme was characterized as a quinoprotein alcohol dehydrogenase.