Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The structure of the chromosomal gene encoding rat aldolase isozyme B has been elucidated by sequence analysis of cloned genomic DNA. This gene comprises about 14 X 10(3) base-pairs of DNA, and is separated into nine exons by eight intervening sequences. A presumed transcription-initiation site was assigned by S1 nuclease protection mapping, and T-A-T-A and C-C-A-A-T boxes were found to be 25 and 126 base-pairs, respectively, upstream from this initiation site. There are three characteristic sequences of 100 to 200 base-pairs within the region of 870 base-pairs flanking the 5' side of the gene. These sequences are flanked on either side by direct repeats and terminate with an A-rich stretch of nucleotides. One of them has block homology with a region in an "ID sequence", which is reported to be an element for tissue-specific gene regulation and differentiation. The other two are analogous at the sequence organizational level with a sort of dispersed repeat, the "Alu family". These features suggest that these regions are involved in gene regulation and, also, imply evolutionary events such as duplication or insertion. Comparison of this gene sequence with the rabbit aldolase A complementary DNA sequence revealed some bias in the frequency of nucleotide replacement among the exons, suggesting selective evolutionary conservation of particular exons encoding functional domains. Comparison with the human aldolase B complementary DNA sequence revealed no such tendency; the homology between the two sequences was very high (about 89%), and nucleotide replacements were randomly distributed throughout the protein-coding region.
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PMID:Structure and genomic organization of the rat aldolase B gene. 258 98

Intrinsic chemical properties of the zinc(II) ion in zinc enzymes have been investigated by the model of 1:1 Zn2+-macrocyclic polyamine complexes, including Zn2+-1,5,9-triazacyclododecane ([12]aneN3) and 1,4,7,10-tetraazacyclododecane (cyclen). The physiologically most suitable pKa values for the Zn2+-bound H2O in enzymes were illustrated by the first model Zn2+-[12]aneN3 complex, which mimics the essential kinetic and thermodynamic roles of Zn2+ in carbonic anhydrase. The activation of proximate serine residues (in alkaline phosphatase) and activation of alcohols for hydride transfer to NAD+ (in alcohol dehydrogenase) were also mimicked by Zn2+ -[12]aneN3 complexes. The functions of two zincs in dinuclear metallophosphatases were explained by a new dinuclear Zn2+-cryptate. For an aldolase type II model, a Zn2+-cyclen derivative showed facile enolate formation from a proximate carbonyl pendant under physiological conditions. The strong anion affinities, which Zn2+ intrinsically possesses, were exploited into novel selective nucleobase thymine (or uracil) recognition of Zn2+-cyclen complexes by the strong Zn2+ -imido anion bond formation. The Zn2+-aromatic-pendant cyclen complexes selectively bind to T (or U) in single- and double-stranded DNA (or RNA). Thus, Zn2+ complexes act like molecular zippers to break A-T pairs in DNA, which was proven by various physicochemical measurements and DNA footprinting assays. These Zn2+ complexes showed some relevant biochemical and biological properties such as inhibition of transcriptional factor, TATA binding protein, or strong antimicrobial activities to gram-positive bacterial strains.
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PMID:Why zinc in zinc enzymes? From biological roles to DNA base-selective recognition. 1081 60