A Poly(oxyethylene)-Supported Cys–Pro–Leu–Cys/Fe(II) Complex as a Rubredoxin Model: Protection of the Fe–Cys Coordination from Hydrolysis in Aqueous Solution

Abstract

ABSTRACT:Hg(II) and Fe(II) complexes of PEG-CO-Cys-Pro-Leu-Cys-OMe (PEG= poly(oxyethylene)) each having an invariant sequence of rubredoxin were synthesized. The complexes were characterized by 13 C NMR and CD spectral methods. In aqueous solution, the Fe(II) complex is considerably resistant to hydrolysis compared to the Fe(Il) complex ofPEG-COCys-OMe because of protection of the Fe(II) core by hydrophobic side chains of Pro and Leu residues.KEY WORDS Fe(II) I Peptide Complex I Polymer-Supported CysContaining Peptide I Rubredoxin Model I X-Ray structural studies of metalloproteins showed their metal ion to be surrounded by a hydrophobic hydrocarbon layer of a certain thickness

Stabilization of hydrolytically labile iron(II)–cysteine peptide thiolate complexes in aqueous triton X-100 micelle solution: Spectroscopic properties mimicking of reduced rubredoxin

“…The repetition rate was Several attempts have been made so far to study 0.1 s. 19 F-nmr spectrum, transients was 2560 and the the properties of the metal complex in an aqueous bandwidth was 100 kHz with the same data points used solution. [23][24][25][26][27][28] The absorption and CD spectra of for the 1 H-nmr spectral measurement. The recycle delay Fe(II) complexes of tetrapeptide ligands, Z-Cys-Xused was 2.0 s. The signal due to tetramethylsilane Y-Cys-OMe (X-Y Å Pro-Leu, Ala-Ala, etc.…”

Improved Preparation of an Amino Acid Type Poly(Ethylene Glycol) Derivative.

“…aaPEG was also prepared from oxidized PEG (oPEG). In this case, oPEG was prepared by oxidation of PEG with potassium permanganate according to the procedure reported by Ueyama et al 6) Since purification of oPEG was problematic, it was difficult to obtain the desired quality of oPEG.…”

Συνθεση Και Μελετη Πεπτιδιων Της Κυστεινης Και Των Συμπλοκων Τους Με Δισθενη Μεταλλικα Ιοντα

“…πεπτιδικής αλυσίδας, ενώ οι υδρόφιλες εντοπίζονται στο εξωτερικό αυτών, μελετήθηκε[225] και η αλληλεπίδραση του Hg(II) με το τετραπεπτίδιο Cys-Pro-Leu-Cys (που περιέχει μεταξύ των κυστεϊνών αμινοξέα υδρόφοβου χαρακτήρα) ενωμένο μέσω της Ν-τελικής αμινομάδας του με πολυμερές πολύ (οξυαιθυλενίου) υδρόφιλου χαρακτήρα. Από τη μελέτη αυτή προκύπτει το συμπέρασμα ότι οι υδρόφοβες ομάδες της πεπτιδικής αλυσίδας περιβάλλοντας τις Et(NH 2 )] έχει επίσης μελετηθεί με φασματοσκοπία IR[236][237][238] και NMR[235,[238][239][240][241].…”