Conformational properties of human and rat apolipoprotein A-IV.
Apolipoprotein A-IV has been isolated from four sources: human and rat lymph and plasma. Conformational properties of the rat and human apoA-IV in solution and denaturation changes induced by guanidine hydrochloride (Gnd X HCl) were studied using circular dichroic and fluorescence spectroscopy, and...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
1985-01-01
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| Series: | Journal of Lipid Research |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520344023 |
| _version_ | 1819055487794020352 |
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| author | E Dvorin W W Mantulin M F Rohde A M Gotto, Jr H J Pownall B C Sherrill |
| author_facet | E Dvorin W W Mantulin M F Rohde A M Gotto, Jr H J Pownall B C Sherrill |
| author_sort | E Dvorin |
| collection | DOAJ |
| description | Apolipoprotein A-IV has been isolated from four sources: human and rat lymph and plasma. Conformational properties of the rat and human apoA-IV in solution and denaturation changes induced by guanidine hydrochloride (Gnd X HCl) were studied using circular dichroic and fluorescence spectroscopy, and analytical sedimentation equilibrium ultracentrifugation. We have shown that both rat and human apoA-IV have similar secondary structure with negative maxima in the circular dichroic spectra at 222 nm and 207 nm. Furthermore, we have found no significant difference in the alpha-helical content of the apoA-IV from rat plasma (33%), rat lymph (37%), human plasma (35%), or human lymph (35%). Our denaturation studies with Gnd X HCl demonstrated reversibility and the fact that each apoA-IV had a tendency to self-associate in solution and the self-association could be disrupted by low concentrations of Gnd X HCl (less than or equal to 0.4 M). Unfolding of the secondary structure of each apoA-IV occurred at higher concentrations of Gnd X HCl (midpoint less than or equal to 1.0 M). The apparent free energy of denaturation of the four apoA-IV proteins calculated from changes in the circular dichroic spectra upon addition of increasing concentrations of Gnd X HCl varied in a range from 3.0 to 4.2 kcal/mol. The fluorescence experiments revealed that apoA-IV from all sources had a maximum fluorescence emission at 342.5 nm, which shifted to the red region upon addition of increasing concentrations of Gnd X HCl.(ABSTRACT TRUNCATED AT 250 WORDS) |
| first_indexed | 2024-12-21T13:08:18Z |
| format | Article |
| id | doaj.art-db8e1298072740979bd49a60052e34a6 |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-12-21T13:08:18Z |
| publishDate | 1985-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Lipid Research |
| spelling | doaj.art-db8e1298072740979bd49a60052e34a62022-12-21T19:02:58ZengElsevierJournal of Lipid Research0022-22751985-01-012613846Conformational properties of human and rat apolipoprotein A-IV.E DvorinW W MantulinM F RohdeA M Gotto, JrH J PownallB C SherrillApolipoprotein A-IV has been isolated from four sources: human and rat lymph and plasma. Conformational properties of the rat and human apoA-IV in solution and denaturation changes induced by guanidine hydrochloride (Gnd X HCl) were studied using circular dichroic and fluorescence spectroscopy, and analytical sedimentation equilibrium ultracentrifugation. We have shown that both rat and human apoA-IV have similar secondary structure with negative maxima in the circular dichroic spectra at 222 nm and 207 nm. Furthermore, we have found no significant difference in the alpha-helical content of the apoA-IV from rat plasma (33%), rat lymph (37%), human plasma (35%), or human lymph (35%). Our denaturation studies with Gnd X HCl demonstrated reversibility and the fact that each apoA-IV had a tendency to self-associate in solution and the self-association could be disrupted by low concentrations of Gnd X HCl (less than or equal to 0.4 M). Unfolding of the secondary structure of each apoA-IV occurred at higher concentrations of Gnd X HCl (midpoint less than or equal to 1.0 M). The apparent free energy of denaturation of the four apoA-IV proteins calculated from changes in the circular dichroic spectra upon addition of increasing concentrations of Gnd X HCl varied in a range from 3.0 to 4.2 kcal/mol. The fluorescence experiments revealed that apoA-IV from all sources had a maximum fluorescence emission at 342.5 nm, which shifted to the red region upon addition of increasing concentrations of Gnd X HCl.(ABSTRACT TRUNCATED AT 250 WORDS)http://www.sciencedirect.com/science/article/pii/S0022227520344023 |
| spellingShingle | E Dvorin W W Mantulin M F Rohde A M Gotto, Jr H J Pownall B C Sherrill Conformational properties of human and rat apolipoprotein A-IV. Journal of Lipid Research |
| title | Conformational properties of human and rat apolipoprotein A-IV. |
| title_full | Conformational properties of human and rat apolipoprotein A-IV. |
| title_fullStr | Conformational properties of human and rat apolipoprotein A-IV. |
| title_full_unstemmed | Conformational properties of human and rat apolipoprotein A-IV. |
| title_short | Conformational properties of human and rat apolipoprotein A-IV. |
| title_sort | conformational properties of human and rat apolipoprotein a iv |
| url | http://www.sciencedirect.com/science/article/pii/S0022227520344023 |
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