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The predicted secondary structures of class I fructose-bisphosphate aldolases.

ABSTRACT: The results of several secondary-structure prediction programs were combined to produce an estimate of the regions of alpha-helix, beta-sheet and reverse turns for fructose-bisphosphate aldolases from human and rat muscle and liver, from Trypanosoma brucei and from Drosophila melanogaster. All the aldolase sequences gave essentially the same pattern of secondary-structure predictions despite having sequences up to 50% different. One exception to this pattern was an additional strongly predicted helix in the rat liver and Drosophila enzymes. Regions of relatively high sequence variation generally were predicted as reverse turns, and probably occur as surface loops. Most of the positions corresponding to exon boundaries are located between regions predicted to have secondary-structural elements consistent with a compact structure. The predominantly alternating alpha/beta structure predicted is consistent with the alpha/beta-barrel structure indicated by preliminary high-resolution X-ray diffraction studies on rabbit muscle aldolase [Sygusch, Beaudry & Allaire (1986) Biophys. J. 49, 287a].

SUBMITTER: Sawyer L

PROVIDER: S-EPMC1148775 | biostudies-other | 1988 Feb

REPOSITORIES: biostudies-other

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Isomer activation controls stereospecificity of class I fructose-1,6-bisphosphate aldolases.

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Highly Selective Inhibitors of Class II Microbial Fructose Bis-phosphate Aldolases.

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A noncompetitive inhibitor for Mycobacterium tuberculosis's class IIa fructose 1,6-bisphosphate aldolase.

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The dhnA gene of Escherichia coli encodes a class I fructose bisphosphate aldolase.

Project description:The gene encoding the Escherichia coli Class I fructose-1, 6-bisphosphate aldolase (FBP aldolase) has been cloned and the protein overproduced in high amounts. This gene sequence has previously been identified as encoding an E. coli dehydrin in the GenBanktrade mark database [gene dhnA; entry code U73760; Close and Choi (1996) Submission to GenBanktrade mark]. However, the purified protein overproduced from the dhnA gene shares all its properties with those known for the E. coli Class I FBP aldolase. The protein is an 8-10-mer with a native molecular mass of approx. 340 kDa, each subunit consisting of 349 amino acids. The Class I enzyme shows low sequence identity with other known FBP aldolases, both Class I and Class II (in the order of 20%), which may be reflected by some novel properties of this FBP aldolase. The active-site peptide has been isolated and the Schiff-base-forming lysine residue (Lys236) has been identified by a combination of site-directed mutagenesis, kinetics and electrospray-ionization MS. A second lysine residue (Lys238) has been implicated in substrate binding. The cloning of this gene and the high levels of overexpression obtained will facilitate future structure-function studies.

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Structure of fructose bisphosphate aldolase from Bartonella henselae bound to fructose 1,6-bisphosphate.

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The proton exchange of the pro-S hydrogen atom at C-1 in dihydroxyacetone phosphate and D-fructose 1,6-bisphosphate catalysed by class-I and class-II aldolases.

Project description:The efficacy of class-I and class-II aldolases in catalysing the C-1 proton exchange in fructose 1,6-bisphosphate and dihydroxyacetone phosphate was investigated. The rate of this reaction was at least two orders of magnitude slower in class-II than in the class-I aldolases. It is suggested that this difference reflects the formation of different intermediates in the reactions catalysed by the two classes of aldolase.

| S-EPMC1183997 | biostudies-other

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