No description available.

Prolidase (E.C.3.4.13.9) hydrolyzes imidodipeptides. Prolidase deficiency (PD) (McKusick no. 170100) is an autosomal recessive disorder characterized by a highly variable clinical phenotype. Mutation analysis was performed on a panel of 10 PD cell lines. Single-stranded conformation polymorphism analysis (SSCP) analysis on four overlapping cDNA-PCR products covering the entire coding region of the prolidase gene revealed seven novel mutations: G $ to$ A,551 (R184Q); G $ to$ A,833 (G278D); G $ to$ A, 1342 (G448R); G $ to$ A, 1354 (E452K); delGAG, 1354-1356 (delE452); a deletion of exon 5; and a deletion of exon 7. We used inverse PCR to clone intronic regions flanking exons 5 and 7 and designed primers for conventional PCR of these regions of the genome in patients expressing mRNAs with deleted exons. Two splice acceptor site mutations were identified: a G $ to$ C, nt $-$1 of intron 4 and an A $ to$ G, nt $-$2 of intron 6. To assess the biochemical phenotypes of four of these mutations (R184Q, G278D, G448R, and delE452), we have designed a transient expression system for prolidase in COS-1 cells. The enzyme was expressed as a fusion protein carrying the HA1 epitope of influenza hemagglutinin, allowing its immunological discrimination from the endogenous enzyme. Expression of the R184Q mutation produced 7.4% of control enzymatic activity while the expression of the G278D, G448R and delE452 produced inactive enzymes. Western analysis of the R184Q, G278D and G448R prolidases revealed stable immunoreactive material whereas the delE452 prolidase was not detectable. Pulse-chase experiments revealed that the delE452 mutant protein was synthesized but unstable. / The R184Q allele is carried by an asymptomatic individual, suggesting that its residual activity may be sufficient to prevent the development of symptoms. The other alleles, G278D, G448R, and delE452 which completely abolish enzyme activity associate with the symptomatic form of the disorder. Interestingly, these substitutions are all located at or very close to the putative metal binding residues of prolidase. / We have cloned and sequenced the mouse prolidase cDNA. We have cloned a genomic DNA fragment which carries exons 2, 3, and 4 of the mouse prolidase gene. We constructed a vector for the targeted disruption of the prolidase gene in mouse embryonic stem cells, to create a mouse model for prolidase deficiency.

No description available.

Dietary zinc deficiency was induced in four healthy male volunteers. The diet used was high in phytate (phytate:zinc molar ratio 381) and the depletion period was preceded by a 3 day starvation period. In the depletion period, there was a significant decrease in plasma zinc and urinary zinc excretion. The subjects also adapted to the low zinc intake by decreasing the faecal excretion of zinc. One subject (No.2) developed clinical signs of zinc deficiency and also had the lowest plasma zinc concentration at the end of the depletion stage. Whole body protein turnover was assessed by an 8hr primed constant infusion of Li-[1-¹³C]leucine. Zinc deficiency had an effect on whole body protein turnover in only one subject (No. 2). In this subject, there was a decrease in leucine oxidation (71%), protein synthesis (31%) and degradation (39%). In this group as a whole, zinc depletion was associated with a significant decrease in urinary excretion of 3-methylhistidine. Zinc deficiency appeared to have no effect on substrate utilization. With regard to zinc kinetics, zinc deficiency was associated with a significant decrease in the size of the plasma zinc pool and a liver pool. There was also a decrease in the flux between these two zinc pools, and an increase in the fractional decay of zinc from the plasma pool to the liver pool. Two further studies were carried out. In 4 volunteers the effect of a 3 day starvation period on whole body protein turnover and zinc kinetics was investigated. There was a significant increase in leucine oxidation and in the size of a liver zinc pool. In 6 volunteers, the effect of phytate on zinc kinetics was investigated. The addition of phytate to the test meal, (phytate:zinc molar ratio 88) was associated with a decrease in the size of a liver zinc pool.

Graduation date: 1980

Master of Dental Surgery / This work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au

Thesis (Ph.D. 1973) from the Dept. of Agricultural Biochemistry and Soil Science, University of Adelaide.

Thesis--PlanA (M.S.)--University of Wisconsin--Stout, 2004. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. Includes: Effects of zinc deficiency in the diets of hens / E.W. Kienholz, D.E. Turk, M.L. Sunde and W.G. Hoekstra. Reprinted from Journal of nutrition, vol. 75, no. 2 (Oct. 1961), p. 211-221. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 90-93).

Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 85-93).