Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2006-3-14
pubmed:abstractText
Nerve growth factor (NGF), a member of the neurotrophin family, is an all-beta-sheet protein with a characteristic structure motif, the cystine knot. Unfolding of NGF in 6 M GdnHCl has been described previously to involve an initial partial loss of structure and a subsequent very slow conversion to a second, completely unfolded state. This latter conversion was postulated to represent a back-threading of the disulfide bond that passes through the cystine knot (loop threading hypothesis). Here, this hypothesis was questioned with the pro form of the protein (proNGF). In proNGF, the mature part is preceded by the 103-amino acid pro-peptide. Consequently, loop threading of the N-terminally extended protein should be significantly delayed. However, unfolding kinetics of proNGF monitored by RP-HPLC, intrinsic fluorescence, and NMR spectroscopy were comparable to those of mature NGF. Time-resolved (1)H-(15)N HSQC spectra revealed a slow time-dependent loss of residual structure of which the kinetics correlated well with the transition observed by RP-HPLC. Refolding from the completely unfolded state led to a partial recovery of natively folded proNGF. In summary, the sequential unfolding of proNGF only marginally differed from that of mature NGF. Therefore, it is very unlikely that a loop threading mechanism is the cause of the slow unfolding step.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
45
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3517-24
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:16533032-Chromatography, High Pressure Liquid, pubmed-meshheading:16533032-Circular Dichroism, pubmed-meshheading:16533032-Cystine, pubmed-meshheading:16533032-Entropy, pubmed-meshheading:16533032-Guanidine, pubmed-meshheading:16533032-Humans, pubmed-meshheading:16533032-Kinetics, pubmed-meshheading:16533032-Nerve Growth Factor, pubmed-meshheading:16533032-Peptides, pubmed-meshheading:16533032-Protein Denaturation, pubmed-meshheading:16533032-Protein Folding, pubmed-meshheading:16533032-Protein Precursors, pubmed-meshheading:16533032-Protein Renaturation, pubmed-meshheading:16533032-Protein Structure, Secondary, pubmed-meshheading:16533032-Protein Structure, Tertiary, pubmed-meshheading:16533032-Recombinant Proteins, pubmed-meshheading:16533032-Spectrometry, Fluorescence, pubmed-meshheading:16533032-Temperature, pubmed-meshheading:16533032-Time Factors
pubmed:year
2006
pubmed:articleTitle
Examination of the slow unfolding of pro-nerve growth factor argues against a loop threading mechanism for nerve growth factor.
pubmed:affiliation
Institut für Biotechnologie der Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Strasse 3, 06120 Halle, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't