Effects of Dimethyl Sulfoxide, Glycerol, and Ethylene Glycol on Secondary Structures of Cytochrome c and Lysozyme As Observed by Infrared Spectroscopy

1995 ◽  
Vol 84 (4) ◽  
pp. 387-392 ◽  
Author(s):  
Ping Huang ◽  
Winslow S. Caughey ◽  
Aichun Dong
Keyword(s):  
Infrared Spectroscopy ◽  
Cytochrome C ◽  
Ethylene Glycol ◽  
Dimethyl Sulfoxide ◽  
Secondary Structures

cis-5-Cyclooctene-1,2-dione and its Ethylene Ketals

1972 ◽  
Vol 50 (10) ◽  
pp. 1548-1556 ◽  
Author(s):  
Peter Yates ◽  
E. G. Lewars ◽  
P. H. McCabe
Keyword(s):  
Hydrogen Peroxide ◽  
Acetic Anhydride ◽  
Ethylene Glycol ◽  
Dimethyl Sulfoxide

Oxidation of cis-cis-1,5-cyclooctadiene with hydrogen peroxide gives cis-5-cyclooctene-trans-1,2-diol (3) which is converted to cis-5-cyclooctene-1,2-dione (6) on treatment with dimethyl sulfoxide and acetic anhydride. Bromination of 6 is accompanied by transannular bonding to give a dibromo keto ether 9a or b. Ketalization of 6 with ethylene glycol gives a monoketal 11 and two diketals 12 and 13 with 1,3-dioxolane and 1,4-dioxane rings, respectively. Bromination of 12 with bromine or pyridinium perbromide is accompanied by transannular bonding and fission of one of the 1,3-dioxolane rings to give a dibromo monoketal ether 15a (or b). Bromination of 12 with N-bromosuccinimide followed by dehydrobromination gives a cyclooctadiene-1,2-dione diketal 20a (or b).

scholarly journals Probing the Proton-Loading Site of Cytochrome C Oxidase Using Time-Resolved Fourier Transform Infrared Spectroscopy

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3393
Author(s):  
Elena Gorbikova ◽  
Sergey A. Samsonov ◽  
Ruslan Kalendar
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Fourier Transform Infrared Spectroscopy ◽  
Paracoccus Denitrificans ◽  
Fourier Transform Infrared ◽  
Double Difference ◽  
Time Resolved ◽  
Fast Kinetic

Crystal structure analyses at atomic resolution and FTIR spectroscopic studies of cytochrome c oxidase have yet not revealed protonation or deprotonation of key sites of proton transfer in a time-resolved mode. Here, a sensitive technique to detect protolytic transitions is employed. In this work, probing a proton-loading site of cytochrome c oxidase from Paracoccus denitrificans with time-resolved Fourier transform infrared spectroscopy is presented for the first time. For this purpose, variants with single-site mutations of N131V, D124N, and E278Q, the key residues in the D-channel, were studied. The reaction of mutated CcO enzymes with oxygen was monitored and analyzed. Seven infrared bands in the “fast” kinetic spectra were found based on the following three requirements: (1) they are present in the “fast” phases of N131V and D124N mutants, (2) they have reciprocal counterparts in the “slow” kinetic spectra in these mutants, and (3) they are absent in “fast” kinetic spectra of the E278Q mutant. Moreover, the double-difference spectra between the first two mutants and E278Q revealed more IR bands that may belong to the proton-loading site protolytic transitions. From these results, it is assumed that several polar residues and/or water molecule cluster(s) share a proton as a proton-loading site. This site can be propionate itself (holding only a fraction of H+), His403, and/or water cluster(s).

scholarly journals Image reconstruction of oxidized cerebral cytochrome C oxidase changes from broadband near-infrared spectroscopy data

2017 ◽  
Vol 4 (2) ◽  
pp. 021105 ◽  
Author(s):  
Sabrina Brigadoi ◽  
Phong Phan ◽  
David Highton ◽  
Samuel Powell ◽  
Robert J. Cooper ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Image Reconstruction ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Spectroscopy Data

Infrared Spectroscopy Studies on Stability of Dimethyl Sulfoxide for Application in a Li–Air Battery

2013 ◽  
Vol 117 (36) ◽  
pp. 18375-18380 ◽  
Author(s):  
Nataliia Mozhzhukhina ◽  
Lucila P. Méndez De Leo ◽  
Ernesto Julio Calvo
Keyword(s):  
Infrared Spectroscopy ◽  
Dimethyl Sulfoxide ◽  
Air Battery ◽  
Spectroscopy Studies

64 CRYOPRESERVATION OF CAT OVARIAN TISSUE BY VITRIFICATION

2013 ◽  
Vol 25 (1) ◽  
pp. 179 ◽  
Author(s):  
J. Galiguis ◽  
C. E. Pope ◽  
M. C. Gómez ◽  
C. Dumas ◽  
S. P. Leibo
Keyword(s):  
Ethylene Glycol ◽  
Dimethyl Sulfoxide ◽  
Ovarian Tissue ◽  
Genetic Material ◽  
Cortical Tissue ◽  
Rock Inhibitor ◽  
Tissue Samples ◽  
Preantral Follicles ◽  
Wide Range ◽  
Chi Square Analysis

The cryopreservation of ovarian tissue is linked to a wide range of possible applications, from oocyte harvesting to allo- and xenotransplantation. These procedures have significant potential for the preservation of valuable genetic material and endangered-species conservation. The objectives of the present study were to (1) compare viability of preantral follicles obtained from fresh v. vitrified feline ovarian cortex, (2) evaluate the effect of apoptotic inhibitors (ROCK inhibitor v. glutathione) on viability of follicles from vitrified samples, and (3) determine the optimal inhibitor concentration for follicle viability. In Experiment 1, 5 × 5 × 1 mm cortical tissue samples were obtained from excised cat ovaries and assigned to either the fresh control or vitrification group. Fresh samples were processed through a 230-micron-pore dissection strainer to collect preantral follicles. Follicles were then stained in Trypan blue to determine membrane integrity and survival rates. Vitrification samples were first equilibrated in 7.5% dimethyl sulfoxide and 7.5% ethylene glycol at ~22°C and then in vitrification solution consisting of 20% dimethyl sulfoxide, 20% ethylene glycol, and 0.5 M sucrose. They were then vitrified on a thin, perforated, metal strip (Cryotissue, Kitazato Biopharma, Fujinomiya, Japan). Samples were later warmed in 1.0 M sucrose at 38°C. Follicles were then collected and assessed for survival. In Experiment 2, follicles were collected from samples vitrified/warmed in cryo-media supplemented with either 3 × 104 nM ROCK inhibitor or 6 nM glutathione. Follicles from samples vitrified/warmed without inhibitor treatment were used as controls. In Experiment 3, tissue samples were vitrified/warmed in cryo-media supplemented with 0, 2, 6, or 10 nM glutathione before follicle viability was determined. Data were evaluated by chi square analysis. In Experiment 1, 637 and 340 follicles were collected from fresh and vitrified samples, respectively. Overall, survival was higher in freshly collected follicles when compared to those from the vitrified group (67 v. 18%, respectively; P < 0.05). Evaluation of apoptotic inhibitors was determined through collection of 314, 354, and 506 follicles from inhibitor-free, ROCK inhibitor, and glutathione-treated media, respectively. Follicles from samples vitrified in inhibitor-free media and in ROCK inhibitor survived at a lower rate than those from glutathione-treated samples (10 and 13% v. 18%, respectively; P < 0.05). In Experiment 3, a total of 539, 641, 625, and 632 follicles were collected from samples treated in 0, 2, 6, and 10 nM glutathione, respectively. There were no statistical differences in follicle survival among the 0, 2, and 6 nM groups. However, follicles treated in 10 nM glutathione survived at a higher rate than those vitrified/warmed in the absence of glutathione (20 v. 14%; P < 0.05). In summary, viability of preantral follicles from ovarian cortical tissue was significantly reduced by vitrification. Despite this, tolerance of such follicles to cryopreservation was improved by vitrifying and warming in cryo-media containing 10 nM glutathione. Partially funded by the LSU/ACRES Collaborative Project.

Sign in / Sign up

Export Citation Format

Share Document