Radiation damage of lysozyme in a biomimetic model: some insights by Raman spectroscopy

Torreggiani, Armida; Tamba, Maurizio; Manco, Immacolata; Faraone-Mennella, Maria Rosaria; Ferreri, Carla; Chatgilialoglu, Chryssostomos

doi:10.1016/j.molstruc.2004.11.076

Cited by 37 publications

(41 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…On the contrary, H • atoms probably attack the enzyme at a more restricted number of sites, perhaps away from the surface and also the far-reaching Tyr can be damaged. A confirm of this behaviour is given by the absence of aggregate formation after H • atom attack [5] , whereas highly aggregated forms of the enzyme have been found under oxidative stress conditions [6,10], since the TyrO • radicals give rise easier to inter-molecular reactions than intra-molecular ones. Since three Tyr "buried" can be probably identified with Tyr-25, -92 and -97, the initial H • radical attack should take place on one or two of them.…”

Section: Resultsmentioning

confidence: 89%

“…In fact, the H • -induced desulfurisation involving these residues yield α-aminobutyrric acid (Abu) and Ala (reactions (5) and (6)). In addition, the reductive radical attack towards Met residues has been recently found to yield diffusible sulfur radicals able inducing damages in cellular membranes [4][5][6]. ,…”

Section: Resultsmentioning

confidence: 99%

“…Since recently the reductive stress has been placed in the context of a biological damage, constituting the basis of tandem-lipid damage the separate contribution of a reducing species such as H • to the changes produced in RNAse was investigated more in detail in the present work [5,6]. Neutral hydrogen atom is a simple one-electron equivalent reducing agent and its reactions are of great interest since they can shed light on basic problems of one-electron equivalent reaction kinetics.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Structural lesion to ribonuclease A caused by reductive stress: Assessment by Raman spectroscopy

Torreggiani

2008

Spectroscopy

Self Cite

View full text Add to dashboard Cite

Abstract. The damages induced by reductive radical stress on bovine pancreatic ribonuclease A (RNAse A) were investigated by Raman spectroscopy. Gamma-irradiation was used to simulate the endogenous formation of reductive species, in particular • H atom that is a simple one-electron equivalent reducing agent. Specific damages occur at sensitive amino acid sites, selectively, rather than indiscriminately, leading to the structure modification of the protein. Sulfur-containing residues (Met and Cys) and aromatic residues are appreciably attacked. In particular, extensive changes in the disulfide bridge conformations are induced as well as conformational changes of the protein secondary structure; a gradual conversion of α-helical to pleated-sheet geometry was evidenced, indicating a higher ability of reducing radicals in denaturing the protein structure compared with that of oxidizing radical species.

show abstract

Section: Resultsmentioning

confidence: 89%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Structural lesion to ribonuclease A caused by reductive stress: Assessment by Raman spectroscopy

Torreggiani

2008

Spectroscopy

Self Cite

View full text Add to dashboard Cite

show abstract

“…A similar trend of conformational changes has been obtained by -irradiation of lysozyme, a protein with analogous molecular weight, the same number of disulfide bridges, and no free thiol groups. 16 It is worth noting that in RNase A the lowest irradiation dose is enough to cause a significant modification of the -helix content (%30%), whereas in lysozyme only a slight change in thehelix percentage was observed under the same conditions (% 3%).…”

mentioning

confidence: 93%

“…Such a biomimetic model of tandem protein-lipid damage was used by us in a previously reported investigation on lysozyme. 16 Indeed, the system showed that the enzyme was particularly resistant to irradiation damage; the effect of lipid damage was also weak. On the contrary, in a preliminary communication on parallel enzyme damage and lipid isomerization, RNase A was shown to have a stronger reactivity, involving in particular sulfurcontaining residues.…”

Section: Introductionmentioning

confidence: 99%

Investigation of radical‐based damage of RNase A in aqueous solution and lipid vesicles

Torreggiani¹,

Tamba²,

Manco

et al. 2005

Biopolymers

Self Cite

View full text Add to dashboard Cite

The gamma-irradiation of bovine pancreatic ribonuclease A (RNase A) in aqueous solution were investigated at different doses by vibrational spectroscopy as well as enzymatic assay, electrophoresis, and HPLC analysis. Both functional and structural changes of the protein were caused by attack of H(*) atoms and (*)OH radicals. In particular, Raman spectroscopy was shown to be a useful tool in identifying conformational changes of the protein structure and amino acidic residues that are preferential sites of the radical attack (i.e., tyrosine and methionine). After partial structural changes by the initial radical attack, the internal sulfur-containing amino acid residues were rendered susceptible to transformation. By using the biomimetic model of dioleoyl phosphatidyl choline vesicle suspensions containing RNase A, the damage to methione residues could be connected to a parallel alteration of membrane unsaturated lipids. In fact, thiyl radical species formed from protein degradation can diffuse into the lipid bilayer and cause isomerization of the naturally occurring cis double bonds. As a consequence, trans unsaturated fatty acids are formed in vesicles and can be considered to be markers of this protein damage.

show abstract

Spectral characterization of lysozyme adsorption on dye‐affinity beads

Başar

Uzun

Güner

et al. 2008

J of Applied Polymer Sci

View full text Add to dashboard Cite

Cibacron Blue F3GA-attached magnetic poly(2-hydroxyethyl methacrylate) [mPHEMA] beads were prepared by suspension polymerization of HEMA in the presence of magnetite (Fe 3 O 4 ) nanopowder. Average diameter size of the mPHEMA beads was 150-200 lm. The characteristic functional groups of Cibacron Blue F3GAattached mPHEMA beads were analyzed by Fourier transform infrared spectrometer (FTIR) and Raman scattering spectrometer. The lysozyme adsorption and desorption characteristics of Cibacron Blue F3GA-attached mPHEMA beads were also investigated using FTIR and Raman spectroscopic techniques. When the Raman spectrum of lyso-zyme adsorbed mPHEMA is evaluated characteristic Amide-I band appears at 1657 cm 21 . The intensity of this band decreases in the spectrum of lysozyme desorbed mPHEMA sample. When the characteristic bands of lysozyme adsorbed and desorbed mPHEMA samples are compared, the band intensities of desorbed sample are lower than those of lysozyme adsorbed sample except for the band appearing at 656 cm 21 (Tyr vCÀ ÀS). EXPERIMENTAL MaterialsLysozyme (chicken egg white, EC 3.2.1.7) and Cibacron Blue F3GA were supplied by Sigma (St. Louis, MO) and used as received. 2-Hydroxyethyl methacry-

show abstract

Radiation damage of lysozyme in a biomimetic model: some insights by Raman spectroscopy

Cited by 37 publications

References 33 publications

Structural lesion to ribonuclease A caused by reductive stress: Assessment by Raman spectroscopy

Structural lesion to ribonuclease A caused by reductive stress: Assessment by Raman spectroscopy

Investigation of radical‐based damage of RNase A in aqueous solution and lipid vesicles

Spectral characterization of lysozyme adsorption on dye‐affinity beads

Contact Info

Product

Resources

About