English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Methylmalonyl-CoA mutase (2-methylmalonyl-CoA CoA-carbonylmutase, EC 5.4.99.2) is a mitochondrial enzyme whose deficiency in man leads to several biochemically and clinically heterogenous++ forms of methylmalonic acidemia. Intact fibroblasts from 21 patients with mutase apoenzyme deficiency have been pulse-labeled with [3H]leucine or [35S]methionine to determine how amounts of newly synthesized mutase recovered from these cells by immunoprecipitation compare with the amounts of steady-state crossreacting material previously determined. Ten lines (3 mut-, 7 mut 0 ), previously shown to have detectable steady-state crossreacting material, had amounts of newly synthesized mutase that varied from similar (7 lines) to considerably greater than (3 lines) the steady-state amounts. Of 11 lines that had no detectable steady-state crossreacting material, 6 had no detectable newly synthesized mutase, and 5 had amounts of mutase ranging from just detectable to almost half that of control. This result suggests that, at least for this latter group, one effect of the mutation in the mutase gene is to reduce the stability of the mutase protein. We examined fibroblasts from 48 patients with mutase apoenzyme deficiency to determine the sizes of the mature mutase subunit and the mutase precursor accumulated in the presence of the mitochondrial transport inhibitor rhodamine 6G. Of the 38 lines that had detectable newly synthesized mutase, only 2, lines 437 and 552, showed a pattern different from that generated by the normal precursor and mature subunits. Line 437 had two immunoprecipitable precursor proteins in the presence of rhodamine, each of which appeared to be transported and processed in the cells to produce two distinct mature proteins. Line 552 also had two anti-mutase reactive proteins in the presence of rhodamine, but each was smaller than the normal mature subunit and neither appeared to be proteolytically processed. The defect in line 552 is almost certainly an amino-terminal deletion that removes the leader peptide necessary for proper uptake and cleavage of the mutase precursor; this represents a clear example of a natural human mutation that interferes with mitochondrial transport of a protein.

proceedings of the national academy of sciences of the united states of america

Immunochemical studies of fibroblasts from patients with methylmalonyl-CoA mutase apoenzyme deficiency: detection of a mutation interfering with mitochondrial import.