The properties of 9 delta-aminolevulinate dehydratase (ALAD) mutants from patients with ALAD porphyria (ADP) were examined by bacterial expression of their complementary DNAs and by enzymologic and immunologic assays. ALADs were expressed as glutathione-S-transferase (GST) fusion proteins in Escherichia coli and purified by glutathione-affinity column chromatography. The GST-ALAD fusion protein...

The properties of 9 d-aminolevulinate dehydratase (ALAD) mutants from patients with ALAD porphyria (ADP) were examined by bacterial expression of their complementary DNAs and by enzymologic and immunologic assays. ALADs were expressed as glutathione-S-transferase (GST) fusion proteins in Escherichia coli and purified by glutathioneaffinity column chromatography. The GSTALAD fusion proteins were...

We have isolated several cDNA clones encoding delta-aminolevulinate dehydrase [ALAD; porphobilinogen synthase; 5-aminolevulinate hydro-lyase (adding 5-aminolevulinate and cyclizing), EC 4.2.1.24], the second enzyme in the heme biosynthetic pathway. We used a rabbit polyclonal antibody developed against the purified 35-kDa subunit of rat liver ALAD to screen a lambda gt11 cDNA expression library...

Delta-aminolevulinate dehydratase (ALAD) catalyzes the second step in the biosynthesis of heme and is also an endogenous inhibitor of the 26S proteasome. The role of ALAD in breast cancer progression is still unclear. In this study, we found that the expression of ALAD was downregulated in breast cancer tissues compared with adjacent normal breast tissues. Enhanced ALAD expression was associate...

Delta-aminolevulinate dehydratase (ALAD) is a phylogenetically conserved enzyme that is responsible for the synthesis of porphobilinogen in a key step involving the production of heme. ALAD is a metalloprotein that requires magnesium or zinc for its activity, depending on the species. In humans, ALAD activity is zinc-dependent, and has been used extensively as a biomarker for lead (Pb) exposure...

The ALAD gene (chromosome 9q34) codes for δ-aminolevulinic acid dehydratase (ALAD) (E.C. 4.2.1.24). ALAD catalyzes the second step of heme synthesis and is polymorphic. The ALAD G177C polymorphism yields two codominant alleles, ALAD-1 and ALAD-2, and it has been implicated in susceptibility to lead toxicity. Genotype frequencies vary by geography and race.The rarer ALAD-2 allele has been associ...

The heme biosynthesis enzyme delta-aminolevulinic acid dehydratase (ALAD) requires magnesium or zinc for activity, depending on the organism, and the heme moiety contains iron. Thus, metals are important for heme formation in at least two different ways. Bradyrhizobium japonicum ALAD* is an engineered derivative of wild-type ALAD that requires Zn2+ for activity rather than Mg2+ (S. Chauhan and ...

Associations between the presence of a constitutional variant of delta-aminolevulinic acid dehydratase (ALAD-2) and lead concentrations in blood and bone, as well as between this allele and indices of kidney function, were investigated among 691 members of a construction trade union. The average blood lead level in this group was 7.78 micrograms/dl. No significant difference was observed in blo...

Previous studies have suggested that delta-aminolevulinic acid dehydratase (ALAD) types 1-2 or 2-2 are protective against the toxicity of blood lead (PbB) when zinc protoporphyrin (ZPP) levels are low because of differential binding of lead in erythrocytes. The hypothesis is that subjects with the ALAD 1-1 genotype are more susceptible to lead exposure with impaired hematologic synthesis and th...

Blood lead levels (BLLs) and delta-aminolevulinic acid dehydratase (ALAD) activity are considered biomarkers of lead exposure and lead toxicity, respectively. The present study was designed to investigate the association between BLLs and ALAD activity in pregnant women from Durango, Mexico. A total of 633 pregnant women aged 13-43 years participated in this study. Blood lead was measured by a g...