1h7d
From Proteopedia
| |||||||
| Activity: | 5-aminolevulinate synthase, with EC number 2.3.1.37 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SOLUTION STRUCTURE OF THE 49 AA PRESEQUENCE OF 5-ALAS
Overview
The mitochondrial import of 5-aminolevulinate synthase (ALAS), the first enzyme of the mammalian heme biosynthetic pathway, requires the N-terminal presequence. The 49 amino acid presequence transit peptide (psALAS) for murine erythroid ALAS was chemically synthesized, and circular dichroism and (1)H nuclear magnetic resonance (NMR) spectroscopies used to determine structural elements in trifluoroethanol/H(2)O solutions and micellar environments. A well defined amphipathic alpha-helix, spanning L22 to F33, was present in psALAS in 50% trifluoroethanol. Further, a short alpha-helix, defined by A5-L8, was also apparent in the 26 amino acid N-terminus peptide, when its structure was determined in sodium dodecyl sulfate. Heme inhibition of ALAS mitochondrial import has been reported to be mediated through cysteine residues in presequence heme regulatory motifs (HRMs). A UV/visible and (1)H NMR study of hemin and psALAS indicated that a heme-peptide interaction occurs and demonstrates, for the first time, that heme interacts with the HRMs of psALAS.
About this Structure
1H7D is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
The solution structure and heme binding of the presequence of murine 5-aminolevulinate synthase., Goodfellow BJ, Dias JS, Ferreira GC, Henklein P, Wray V, Macedo AL, FEBS Lett. 2001 Sep 14;505(2):325-31. PMID:11566198
Page seeded by OCA on Thu Mar 20 11:33:18 2008
