creators_name: Dave, Sandeep
creators_name: Mahajan, Sahil
creators_name: Chandra, Vemika
creators_name: Dkhar, H Kitdorlang
creators_name: Sambhavi, -
creators_name: Gupta, Pawan
type: article
datestamp: 2011-12-08 19:18:04
lastmod: 2011-12-08 19:18:04
metadata_visibility: show
title: Specific molten globule conformation of stem bromelain at alkaline pH.
ispublished: pub
subjects: QR
full_text_status: none
keywords: Protein folding; Alkaline denaturation; Bromelain; Molten globule; Temperature endotherm; Thermodynamics
note: Copyright of this article belongs to Elsevier Science
abstract: Stem bromelain (SBM), a therapeutic protein, is rapidly absorbed across the gut epithelium. Because SBM encounters an alkaline pH at its principal site of absorption, we investigated the alkaline-induced denaturation of SBM. From pH 7 to 10, the protein's secondary structure remained the same, although a slight loss of tertiary structure was observed. Above pH 10, there was a significant and irreversible loss of secondary and tertiary structure. At pH 10, SBM showed enhanced tryptophan fluorescence, however, the number of accessible tryptophans remained the same. The thermodynamics of temperature transition at pH 7 and 10 were strikingly different, with the former showing a two-phase transition endotherm, and the latter a broad non-two-state transition. At pH 10, SBM showed a significant increase in 8-anilino-1-naphthalene-sulfonate binding relative to the native state, suggestive of a specific molten globule (SMG) state. These studies suggest a distinct conformational rearrangement in SBM, at the protein's isoelectric point.
date: 2010-07
date_type: published
publication: Archives of biochemistry and biophysics
volume: 499
number: 1-2
publisher: Elsevier Science
pagerange: 26-31
refereed: TRUE
issn: 1096-0384
official_url: http://www.sciencedirect.com/science/article/pii/S0003986110001724
related_url_url: http://www.sciencedirect.com/science/article/pii/S0003986110001724
related_url_type: pub
citation:   Dave, Sandeep and Mahajan, Sahil and Chandra, Vemika and Dkhar, H Kitdorlang and Sambhavi, - and Gupta, Pawan  (2010) Specific molten globule conformation of stem bromelain at alkaline pH.  Archives of biochemistry and biophysics, 499 (1-2).  pp. 26-31.  ISSN 1096-0384