In pre-sterol carrier protein 2 (SCP2) in solution the leader peptide 1-20 is flexibly disordered, and residues 21-143 adopt the same globular fold as in mature SCP2.
The preform of the rabbit sterol carrier protein 2 (pre-rSCP2) was cloned, the uniformly 15N-labelled protein expressed in Escherichia coli and studied by three-dimensional 15N-resolved nuclear magnetic resonance spectroscopy. In spite of its low solubility in aqueous solution of only approximately 0.3 mM, sequential 15N and 1H backbone resonance assignments were obtained for 105 out of the 143 residues. From comparison of the sequential and medium-range nuclear Overhauser effects (NOEs) in the two proteins, all regular secondary structures previously determined in mature human SCP2 (hSCP2) [Szyperski et al. (1993) FEBS Lett. 335: 18-26] were also identified in pre-rSCP2. Near-identity of the backbone 15N and 1H chemical shifts and 1:1 correspondence of 24 long-range NOEs to backbone amide groups in the two proteins show that the residues 21-143 adopt the same globular fold in pre-rSCP2 and mature hSCP2. The N-terminal 20-residue leader peptide of pre-rSCP2 is flexibly disordered in solution and does not observably affect the conformation of the polypeptide segment 21-143.
Institut für Biochemie, Eidgenössische Technische Hochschule-Zentrum, Zürich, Switzerland.
F E
FE
Weber
J H
JH
Dyer
F
F
López García
M
M
Werder
T
T
Szyperski
K
K
Wüthrich
H
H
Hauser
D000595:Amino Acid Sequence; D000818:Animals; D018797:Cell Cycle Proteins / Q000737:chemistry*; D002784:Cholesterol / Q000378:metabolism; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000737:chemistry*; D007700:Kinetics; D008081:Liposomes / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017510:Protein Folding; D011498:Protein Precursors / Q000737:chemistry*; D021382:Protein Sorting Signals / Q000737:chemistry*; D017433:Protein Structure, Secondary; D011817:Rabbits; D011994:Recombinant Proteins / Q000737:chemistry; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D008081:Liposomes; D011498:Protein Precursors; D021382:Protein Sorting Signals; D011994:Recombinant Proteins; C113093:Sycp2 protein, rat; D002784:Cholesterol