Purification and characterization of hepatic porcine gluconolactonase

Roberts, Billy D.; Bailey, George D.; Buess, Charles M.; Carper, W. Robert

doi:10.1016/0006-291x(78)90173-0

Cited by 22 publications

(7 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Its native molecular size of 90,000 Da is lower than that of the liver enzyme, which is described as a hexamer (18). It is possible that the Z. mobilis gluconolactonase is a trimer, although the subunit size would be different from that of the liver enzyme.…”

Section: Discussionmentioning

confidence: 99%

Glucose-fructose oxidoreductase, a new enzyme isolated from Zymomonas mobilis that is responsible for sorbitol production

Zachariou¹,

Scopes²

1986

J Bacteriol

182

156

View full text Add to dashboard Cite

The enzymes responsible for sorbitol formation in Zymomonas mobiis were investigated. A previously undescribed enzyme catalyzes the intermolecular oxidation-reduction of glucose and fructose to form gluconolactone and sorbitol. This enzyme has been purified; it had a subunit size of 40,000 daltons and is probably tetrameric at low pH. It contained tightly bound NADP as the hydrogen carrier and did not require any added cofactor for activity. In addition, a gluconolactonase has been isolated, although not completely purified. Together these two enzymes were capable of completely converting a 54% (wt/vol) equimolar mixture of glucose and fructose to sorbitol and sodium gluconate at the optimum pH of close to 6.2. The oxidoreductase had low affinities for its substrates, but natural environmental conditions would expose it to high concentrations of sugars. The amount of the enzyme in Z. mobilis cells was sufficient to account for the rate of sorbitol formation in vivo. However, the enzyme was present in the highest amounts when the cells were grown on glucose alone, and it was repressed by the presence of fructose; this was not the case with the gluconolactonase.In 1984 it was noted that among the fermentation products of the ethanol producer Zymomonas mobilis, sorbitol accumulated to quite high levels when sucrose or a mixture of glucose and fructose was used as the carbon source (5). The carbon skeleton of sorbitol was shown to derive exclusively from fructose. Several possible enzymatic routes for sorbitol production have been suggested (23, 24); however, the levels of the proposed enzymes in extracts of Z. mobilis were far too low to account for the rate of sorbitol production in vivo. We proposed (16) that two dehydrogenases acting through an unknown bound cofactor were responsible for the dehydrogenation of glucose to gluconolactone, followed by the reduction of fructose to sorbitol. Although the activity of a glucose dehydrogenase measured with an artificial acceptor such as ferricyanide or dichlorophenolindophenol was equivalent to the required activity, there remained doubts about its role in sorbitol production because of the differing sugar specificities of the two processes. Nevertheless, an extract of cells, even after removal of endogenous salts and cofactors, was capable of reaction with glucose and fructose (and no other combination of sugars) to produce both sorbitol and gluconic acid without any added cofactor.In this paper we show that sorbitol and gluconolactone production from fructose and glucose in Z. mobilis is catalyzed by a single enzyme containing tightly bound NADP. In addition, there is a gluconolactonase (EC 3.1.1.17) which accelerates hydrolysis of the unstable lactone. The new enzyme has provisionally been named D-glucose-l:D-fructose-2-oxidoreductase. It has been purified, and information on its structural and kinetic properties was obtained. In the same purification procedure, gluconolactonase has also been isolated, although not fully purified.The glucose-fructose oxidoreductase t...

show abstract

Section: Discussionmentioning

confidence: 99%

Glucose-fructose oxidoreductase, a new enzyme isolated from Zymomonas mobilis that is responsible for sorbitol production

Zachariou¹,

Scopes²

1986

J Bacteriol

182

156

View full text Add to dashboard Cite

show abstract

“…Among those characterized lactonases, the gluconolactonase of porcine liver and the lactonohydrolase from Fusarium oxysporum require divalent metal ions for activity and are inhibited by metal-chelating reagents (40,41), whereas others, such as 4-and 5-pyridocolactonase and hydroxyglutaric acid lactonase, are independent of such ions for activity (37,38). AHL-lactonase appears to belong to the latter.…”

Section: Kinetics and Circular Dichroism Analysis Of Ahl-lactonase Vamentioning

confidence: 99%

Specificity and Enzyme Kinetics of the Quorum-quenching N-Acyl Homoserine Lactone Lactonase (AHL-lactonase)

Wang

Weng

Dong

et al. 2004

Journal of Biological Chemistry

198

205

View full text Add to dashboard Cite

N-Acyl homoserine lactone (AHL) quorum-sensing signals are the vital elements of bacterial quorum-sensing systems, which regulate diverse biological functions, including virulence. The AHL-lactonase, a quorumquenching enzyme encoded by aiiA from Bacillus sp., inactivates AHLs by hydrolyzing the lactone bond to produce corresponding N-acyl homoserines. To characterize the enzyme, the recombinant AHL-lactonase and its four variants were purified. Kinetic and substrate specificity analysis showed that AHL-lactonase had no or little residue activity to non-acyl lactones and noncyclic esters, but displayed strong enzyme activity toward all tested AHLs, varying in length and nature of the substitution at the C3 position of the acyl chain. The data also indicate that the amide group and the ketone at the C1 position of the acyl chain of AHLs could be important structural features in enzyme-substrate interaction. Surprisingly, although carrying a 104 HX-HXDH 109 short sequence identical to the zinc-binding motif of several groups of metallohydrolytic enzymes, AHL-lactonase does not contain or require zinc or other metal ions for enzyme activity. Except for the amino acid residue His-104, which was shown previously to not be required for catalysis, kinetic study and conformational analysis using circular dichroism spectrometry showed that substitution of the other key residues in the motif (His-106, Asp-108, and His-109), as well as His-169 with serine, respectively, caused conformational changes and significant loss of enzyme activity. We conclude that AHL-lactonase is a highly specific enzyme and that the 106 HXDH 109 ϳH 169 of AHL-lactonase represents a novel catalytic motif, which does not rely on zinc or other metal ions for activity.Many host-associated bacteria produce, release, and respond to small signal molecules to monitor their own population density and control the expression of specific genes in response to change in population density. This type of gene regulation, which controls diverse biological functions including virulence and biofilm formation, is known as quorum-sensing (QS) 1 (1-4). In general, each individual bacterial cell produces a basal level of QS signals. The signals accumulate to a threshold concentration as the cells proliferate and interact with their cognate transcription factors to activate gene expression. Several groups of QS signals have been identified. Among them, N-acyl homoserine lactones (AHLs) comprise a family of QS signals identified in many Gram-negative bacteria, in particular, Proteobacteria. Different bacterial species may produce different AHLs, which vary in the length and substitution of the acyl chain but maintain the same homoserine lactone moiety (1, 3, 4). These structural variations could constitute the basis of signaling specificity of AHL molecules (5, 6).The AHL-dependent QS system has drawn considerable attention over the last 10 years, as it is involved in the regulation of diverse and important biological functions, in particular, the virulence gene expressi...

show abstract

“…Also known is that GL exists in microbial cells such as yeast and E. coli and in animal tissues such as porcine liver. The purification of GL has been performed by many researchers, − most of them reporting enzyme characteristics such as optimal pH and temperature, as well as a role of the enzyme in metabolic systems such as hepatic glycogen degradation. In particular, it is important that the turnover of GL is 13000 min -1 (ref ), the value of which is much higher than the rate constant (0.01 min -1 ) of the thermal hydrolysis of δ-DGL .…”

Section: Introductionmentioning

confidence: 99%

Coimmobilization of Gluconolactonase with Glucose Oxidase for Improvement in Kinetic Property of Enzymatically Induced Volume Collapse in Ionic Gels

et al. 2002

View full text Add to dashboard Cite

The object of this paper is to provide an enzymatic means to attain faster swelling or shrinking kinetics of polyelectrolyte gels that undergo volume phase transition as an immobilized enzyme reaction sets in. For this, we studied the coimmobilization of gluconolactonase (GL) with glucose oxidase (GOD). A gel used was in the shape of a small cylinder (several hundred micrometers in diameter) and composed of a lightly cross-linked copolymer of N-isopropylacrylamide and acrylic acid. GL was isolated from Aspergillus niger and purified about 100-fold. It was found that in a substrate solution containing glucose, the gel with the coimmobilized GL and GOD shrinks very rapidly. The shrinking rate was identical to that of the enzyme-free gel that undergoes a shrinking transition in response to a sudden pH change of the outer medium from 7 to 5. This indicates the rate-limiting step in the shrinking process to be diffusion of the networks, but not the enzyme reaction. In the gel with singly immobilized GOD, a very slow shrinking was observed because the process is governed by the enzyme reaction. These results were discussed in full in connection with an enzymatically induced decrease in pH within and in the vicinity of the gel phase. As a result, it has become apparent that the faster shrinking kinetics in the coimmobilized enzyme system is attained by the GL-catalyzed hydrolysis of D-glucono-delta-lactone resulting from the oxidation of glucose with GOD.

show abstract

Purification and characterization of hepatic porcine gluconolactonase

Cited by 22 publications

References 24 publications

Glucose-fructose oxidoreductase, a new enzyme isolated from Zymomonas mobilis that is responsible for sorbitol production

Glucose-fructose oxidoreductase, a new enzyme isolated from Zymomonas mobilis that is responsible for sorbitol production

Specificity and Enzyme Kinetics of the Quorum-quenching N-Acyl Homoserine Lactone Lactonase (AHL-lactonase)

Coimmobilization of Gluconolactonase with Glucose Oxidase for Improvement in Kinetic Property of Enzymatically Induced Volume Collapse in Ionic Gels

Contact Info

Product

Resources

About