The first step of hen egg white lysozyme fibrillation, irreversible partial unfolding, is a two‐state transition

Xu, Min; Shashilov, Victor A.; Ermolenkov, Vladimir V.; Fredriksen, Laura; Zagorevski, Dmitri V.; Lednev, Igor K.

doi:10.1110/ps.062639307

Cited by 65 publications

(71 citation statements)

References 112 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has been previously reported that the random component of the secondary structure plays a relevant role in the fibrillation process, as in the first stage of the fibrillation the native structure falls in a disordered structure and then develops into an organized β inter-chain structure. 62 It is important to recall that the peak at around 1670 cm -1 is the marker of ordered β sheet structures in the aggregated sample, and that this feature together with the narrowing of the amide I band are the most clear markers of fibril formation in the Raman spectra. 63 Shifts at lower frequencies can be observed in the amide III region coherently with the above mentioned changes in the secondary structure from α helix (around 1300 cm -1 ) toward ordered β sheet (around 1230 cm -1 ) (see Fig.…”

Section: 49mentioning

confidence: 99%

Role of ionic liquids in protein refolding: native/fibrillar versus treated lysozyme

et al. 2012

View full text Add to dashboard Cite

Several ionic liquids (ILs) are known to revert aggregation processes and improve the in vitro refolding of denatured proteins. In this paper the capacity of a particular class of ammonium based ILs to act as refolding enhancers was tested using lysozyme as a model protein. Raman spectra of ILs treated fibrillar lysozyme as well as lysozyme in its native and fibrillar conformations were collected and carefully analyzed to characterize the refolding extent under the effect of the IL interaction. Results obtained confirm and largely extend the earlier knowledge on this class of protic ILs and indicate Ethyl Ammonium Nitrate (EAN) as the most promising additive for protein refolding. The experiment provides also the demonstration of the high potentiality of Raman spectroscopy as a comprehensive diagnostic tool in this field. IntroductionProtein aggregation is one of the most important problems in the production and storage industrial processes and therefore among the causes of the major economic loss in biotechnology and pharmaceutical factories. Indeed in manufacturing commercial products, the goal is to obtain a stable and correct protein folding for allowing the full functionality. 1 The problems of protein aggregation and structural stability are not limited to the manufacturing processes. Protein misfolding diseases are a well-known class of ailments including Alzheimer, Parkinson and Huntington diseases. They all involve protein aggregation and share common features such as the presence of insoluble fibrous protein aggregation in a specific structural motif characterized by a cross-β sheet structure. 2 Key issues on aggregation are not yet fully addressed such as the detailed microscopic mechanism leading to aggregation, the structure of aggregates, how the environmental conditions can affect the rate and the amount of aggregation and how aggregation can be prevented and/or removed. Additives may promote the stabilization of the native state of the protein accelerating the kinetics of the correct folding and removing/inhibiting the aggregation of denatured polypeptides and intermediates of the folding pathways. 3In recent years ionic liquids (ILs) have been used to stabilize the protein activity, to inhibit or reduce aggregation, and to improve the in vitro refolding of denatured proteins. 4,5 ILs have numerous attractive characteristics including their non-volatility, good solvating properties, thermal stability, and recyclability, that render these compounds "environmentally green". 6,7,8,9,10 One of the most important qualities of these solvents is the high tunability of their chemical structure. Indeed, they can be designed to have specific physical and chemical qualities by acting on either the alkyl chains (i.e. modifying the length, the presence of hydrophobic groups, etc.) or the anion (i.e. varying the degree of the charge delocalization, its hydrogen bonding ability, etc). 11 ILs having coordinating anions which are strong hydrogen bond acceptors (e.g. Cl − , NO 3 − , CH 3 COO − and (MeO) 2 PO 2 − )...

show abstract

Section: 49mentioning

confidence: 99%

Role of ionic liquids in protein refolding: native/fibrillar versus treated lysozyme

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Advanced statistical methods allow for retrieving of reliable information from data sets that is not otherwise evident. We have been successful in developing and applying advanced statistical analysis of Raman spectra for biochemical [19][20][21][22][23][24][25][26][27] and forensic purposes [7][8][9]11,13].…”

Section: Open Accessmentioning

confidence: 99%

Discriminant Analysis of Raman Spectra for Body Fluid Identification for Forensic Purposes

Sikirzhytski

Virkler

Lednev

et al. 2010

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

Detection and identification of blood, semen and saliva stains, the most common body fluids encountered at a crime scene, are very important aspects of forensic science today. This study targets the development of a nondestructive, confirmatory method for body fluid identification based on Raman spectroscopy coupled with advanced statistical analysis. Dry traces of blood, semen and saliva obtained from multiple donors were probed using a confocal Raman microscope with a 785-nm excitation wavelength under controlled laboratory conditions. Results demonstrated the capability of Raman spectroscopy to identify an unknown substance to be semen, blood or saliva with high confidence.

show abstract

“…spectroscopy. We plan to apply advanced statistical methods, chemometrics in particular [88,89], to extract structural information from the spectroscopic data.…”

Section: Quantification Of Secondary Structural Transitionmentioning

confidence: 99%

“…This indicated that the partial unfolding of lysozyme is an all-or-none transition, i.e. two-state transition [88].…”

mentioning

confidence: 99%

Hen egg white lysozyme fibrillation: a deep‐UV resonance Raman spectroscopic study

Ermolenkov

Uversky

et al. 2008

Journal of Biophotonics

Self Cite

View full text Add to dashboard Cite

Amyloid fibrils are associated with numerous degenerative diseases. The molecular mechanism of the structural transformation of native protein to the highly ordered cross-beta structure, the key feature of amyloid fibrils, is under active investigation. Conventional biophysical methods have limited application in addressing the problem because of the heterogeneous nature of the system. In this study, we demonstrated that deep-UV resonance Raman (DUVRR) spectroscopy in combination with circular dichroism (CD) and intrinsic tryptophan fluorescence allowed for quantitative characterization of protein structural evolution at all stages of hen egg white lysozyme fibrillation in vitro. DUVRR spectroscopy was found to be complimentary to the far-UV CD because it is (i) more sensitive to beta -sheet than to alpha -helix, and (ii) capable of characterizing quantitatively inhomogeneous and highly light-scattering samples. In addition, phenylalanine, a natural DUVRR spectroscopic biomarker of protein structural rearrangements, exhibited substantial changes in the Raman cross section of the 1000-cm(-1) band at various stages of fibrillation.

show abstract

The first step of hen egg white lysozyme fibrillation, irreversible partial unfolding, is a two‐state transition

Cited by 65 publications

References 112 publications

Role of ionic liquids in protein refolding: native/fibrillar versus treated lysozyme

Role of ionic liquids in protein refolding: native/fibrillar versus treated lysozyme

Discriminant Analysis of Raman Spectra for Body Fluid Identification for Forensic Purposes

Hen egg white lysozyme fibrillation: a deep‐UV resonance Raman spectroscopic study

Contact Info

Product

Resources

About