New insights into the structural characteristics of irradiated crotamine
Abstract Background: Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crota...
Published in: | Journal of Venomous Animals and Toxins including Tropical Diseases |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
SciELO
2015
|
Subjects: | |
Online Access: | https://doi.org/10.1186/s40409-015-0013-z https://doaj.org/article/c92457a2d20347b8a36738865e66ad26 |
id |
ftdoajarticles:oai:doaj.org/article:c92457a2d20347b8a36738865e66ad26 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:c92457a2d20347b8a36738865e66ad26 2023-05-15T15:15:55+02:00 New insights into the structural characteristics of irradiated crotamine Karina Corleto Oliveira Patrick Jack Spencer Rui Seabra Ferreira Jr Nanci Nascimento 2015-08-01T00:00:00Z https://doi.org/10.1186/s40409-015-0013-z https://doaj.org/article/c92457a2d20347b8a36738865e66ad26 EN eng SciELO http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992015000100321&lng=en&tlng=en https://doaj.org/toc/1678-9199 1678-9199 doi:10.1186/s40409-015-0013-z https://doaj.org/article/c92457a2d20347b8a36738865e66ad26 Journal of Venomous Animals and Toxins including Tropical Diseases, Vol 21, Iss 0 (2015) Gamma radiation Structural modifications Crotamine Snake venom Crotalus durissus terrificus Arctic medicine. Tropical medicine RC955-962 Toxicology. Poisons RA1190-1270 Zoology QL1-991 article 2015 ftdoajarticles https://doi.org/10.1186/s40409-015-0013-z 2022-12-31T14:58:52Z Abstract Background: Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crotamine, a toxin from Crotalus durissus terrificus venom, using circular dichroism (CD), fluorescence, Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Methods: A combination of size exclusion and ion-exchange chromatography was used to purify the peptide using crude venom. The pure toxin was then submitted to 2 kGy gamma irradiation doses from a cobalt-60 source. Native and irradiated crotamine were analyzed using a fluorescence spectrophotometer. Wavelength was fixed at 295 nm and fluorescence emission scans were collected from 300 to 400 nm. CD and FTIR techniques were used to identify the secondary structure of both samples. DSC analyses were performed at a starting temperature of 20 °C up to a final temperature of 90 °C. AFM provided a 3D profile of the surfaces of both crotamine forms adsorbed on mica. Results: Fluorescence spectroscopy showed that the quantum yield of the irradiated form decreased. CD spectra of native and irradiated crotamine solutions showed differences between the samples in wavelength, indicating that irradiation induced a transition of a small portion of the random coil regions towards an a-helical conformation. FTIR and CD showed that the native and irradiated crotamine spectra were different with regard to secondary structure. The thermodynamic analysis showed that irradiation caused changes in the calorimetric profile and CD showed that temperature-induced changes also occur in the secondary structure. Finally, AFM showed the possible formation of insoluble aggregates. Conclusions: Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain a decrease in ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic Journal of Venomous Animals and Toxins including Tropical Diseases 21 1 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Gamma radiation Structural modifications Crotamine Snake venom Crotalus durissus terrificus Arctic medicine. Tropical medicine RC955-962 Toxicology. Poisons RA1190-1270 Zoology QL1-991 |
spellingShingle |
Gamma radiation Structural modifications Crotamine Snake venom Crotalus durissus terrificus Arctic medicine. Tropical medicine RC955-962 Toxicology. Poisons RA1190-1270 Zoology QL1-991 Karina Corleto Oliveira Patrick Jack Spencer Rui Seabra Ferreira Jr Nanci Nascimento New insights into the structural characteristics of irradiated crotamine |
topic_facet |
Gamma radiation Structural modifications Crotamine Snake venom Crotalus durissus terrificus Arctic medicine. Tropical medicine RC955-962 Toxicology. Poisons RA1190-1270 Zoology QL1-991 |
description |
Abstract Background: Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crotamine, a toxin from Crotalus durissus terrificus venom, using circular dichroism (CD), fluorescence, Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Methods: A combination of size exclusion and ion-exchange chromatography was used to purify the peptide using crude venom. The pure toxin was then submitted to 2 kGy gamma irradiation doses from a cobalt-60 source. Native and irradiated crotamine were analyzed using a fluorescence spectrophotometer. Wavelength was fixed at 295 nm and fluorescence emission scans were collected from 300 to 400 nm. CD and FTIR techniques were used to identify the secondary structure of both samples. DSC analyses were performed at a starting temperature of 20 °C up to a final temperature of 90 °C. AFM provided a 3D profile of the surfaces of both crotamine forms adsorbed on mica. Results: Fluorescence spectroscopy showed that the quantum yield of the irradiated form decreased. CD spectra of native and irradiated crotamine solutions showed differences between the samples in wavelength, indicating that irradiation induced a transition of a small portion of the random coil regions towards an a-helical conformation. FTIR and CD showed that the native and irradiated crotamine spectra were different with regard to secondary structure. The thermodynamic analysis showed that irradiation caused changes in the calorimetric profile and CD showed that temperature-induced changes also occur in the secondary structure. Finally, AFM showed the possible formation of insoluble aggregates. Conclusions: Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain a decrease in ... |
format |
Article in Journal/Newspaper |
author |
Karina Corleto Oliveira Patrick Jack Spencer Rui Seabra Ferreira Jr Nanci Nascimento |
author_facet |
Karina Corleto Oliveira Patrick Jack Spencer Rui Seabra Ferreira Jr Nanci Nascimento |
author_sort |
Karina Corleto Oliveira |
title |
New insights into the structural characteristics of irradiated crotamine |
title_short |
New insights into the structural characteristics of irradiated crotamine |
title_full |
New insights into the structural characteristics of irradiated crotamine |
title_fullStr |
New insights into the structural characteristics of irradiated crotamine |
title_full_unstemmed |
New insights into the structural characteristics of irradiated crotamine |
title_sort |
new insights into the structural characteristics of irradiated crotamine |
publisher |
SciELO |
publishDate |
2015 |
url |
https://doi.org/10.1186/s40409-015-0013-z https://doaj.org/article/c92457a2d20347b8a36738865e66ad26 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
Journal of Venomous Animals and Toxins including Tropical Diseases, Vol 21, Iss 0 (2015) |
op_relation |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992015000100321&lng=en&tlng=en https://doaj.org/toc/1678-9199 1678-9199 doi:10.1186/s40409-015-0013-z https://doaj.org/article/c92457a2d20347b8a36738865e66ad26 |
op_doi |
https://doi.org/10.1186/s40409-015-0013-z |
container_title |
Journal of Venomous Animals and Toxins including Tropical Diseases |
container_volume |
21 |
container_issue |
1 |
_version_ |
1766346244482924544 |