In a previous study we have shown that bringing horseradish peroxidase to pH 3.0 induces a spectroscopic transition (G. Smulevich et al., Biochemistry 36 (1997) 640). We have extended the investigation on this pH-Iinked conformational change to different experimental conditions, such as (i) in phosphate alone, (ii) in HCl alone and (iii) in phosphate + NaCl. The data obtained allow a number of conclusions to be drawn, namely: (a) the exposure to ph 3.0 under all conditions brings about an alteration of the distal portion of the heme pocket, leading to the rapid formation of a hexa-coordinated species; (b) only in the presence of phosphate is the hexa-coordination followed by a slow cleavage (or severe weakening) of the proximal Fe-His bond, and (c) the rate of this second process is speeded up in the presence of Cl- ions. Such observations underline the presence of a communication pathway between the two opposite sides of the heme pocket, such that any alteration of the structural arrangement on one side of the heme cavity is transmitted to the other, inducing a corresponding conformational change. (C) 2000 Elsevier Science Inc. All rights reserved.

Priori, A.m., Indiani, C., De Sanctis, G., Marini, S., Santucci, R., Smulevich, G., et al. (2000). Anion- and pH-linked conformational transition in horseradish peroxidase. In Journal of Inorganic Biochemistry (pp.25-30). NEW YORK : ELSEVIER SCIENCE INC [10.1016/S0162-0134(99)00229-9].

Anion- and pH-linked conformational transition in horseradish peroxidase

MARINI, STEFANO;SANTUCCI, ROBERTO;COLETTA, MASSIMILIANO
2000

Abstract

In a previous study we have shown that bringing horseradish peroxidase to pH 3.0 induces a spectroscopic transition (G. Smulevich et al., Biochemistry 36 (1997) 640). We have extended the investigation on this pH-Iinked conformational change to different experimental conditions, such as (i) in phosphate alone, (ii) in HCl alone and (iii) in phosphate + NaCl. The data obtained allow a number of conclusions to be drawn, namely: (a) the exposure to ph 3.0 under all conditions brings about an alteration of the distal portion of the heme pocket, leading to the rapid formation of a hexa-coordinated species; (b) only in the presence of phosphate is the hexa-coordination followed by a slow cleavage (or severe weakening) of the proximal Fe-His bond, and (c) the rate of this second process is speeded up in the presence of Cl- ions. Such observations underline the presence of a communication pathway between the two opposite sides of the heme pocket, such that any alteration of the structural arrangement on one side of the heme cavity is transmitted to the other, inducing a corresponding conformational change. (C) 2000 Elsevier Science Inc. All rights reserved.
5th International Symposium on Applied Bioinorganic Chemistry (5 ISABC)
CORFU, GREECE
APR 13-17, 1999
European Cooperat Field Sci & Tech Res, Greek Minist Culture, Greek Minist Educ, Univ Ioannina, Minist Ind, Gen Secretariat Res & Technol
Rilevanza internazionale
Settore BIO/10
English
Absorption spectroscopy; Chloride effects; Horseradish peroxidase; pH effects; Resonance Raman spectroscopy
Intervento a convegno
Priori, A.m., Indiani, C., De Sanctis, G., Marini, S., Santucci, R., Smulevich, G., et al. (2000). Anion- and pH-linked conformational transition in horseradish peroxidase. In Journal of Inorganic Biochemistry (pp.25-30). NEW YORK : ELSEVIER SCIENCE INC [10.1016/S0162-0134(99)00229-9].
Priori, Am; Indiani, C; De Sanctis, G; Marini, S; Santucci, R; Smulevich, G; Coletta, M
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/53085
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact