Publication:
Influence of Fluorocarbon and Hydrocarbon Acyl Groups at the Surface of Bovine Carbonic Anhydrase II on the Kinetics of Denaturation by Sodium Dodecyl Sulfate

Thumbnail Image

Date

2011

Published Version

Journal Title

Journal ISSN

Volume Title

Publisher

American Chemical Society (ACS)
The Harvard community has made this article openly available. Please share how this access benefits you.

Research Projects

Organizational Units

Journal Issue

Citation

Lee, Andrew, Katherine A. Mirica, and George M. Whitesides. 2011. “Influence of Fluorocarbon and Hydrocarbon Acyl Groups at the Surface of Bovine Carbonic Anhydrase II on the Kinetics of Denaturation by Sodium Dodecyl Sulfate.” The Journal of Physical Chemistry B 115, no. 5: 1199–1210.

Research Data

Abstract

This paper examines the influence of acylation of the Lys-ε-NH3+ groups of bovine carbonic anhydrase (BCA, EC 4.2.1.1) to Lys-ε-NHCOR (R = −CH3, −CH2CH3, and −CH(CH3)2, −CF3) on the rate of denaturation of this protein in buffer containing sodium dodecyl sulfate (SDS). Analysis of the rates suggested separate effects due to electrostatic charge and hydrophobic interactions. Rates of denaturation (kAc,n) of each series of acylated derivatives depended on the number of acylations (n). Plots of log kAc,n vs n followed U-shaped curves. Within each series of derivatives, rates of denaturation decreased as n increased to 7; this decrease was compatible with increasingly unfavorable electrostatic interactions between SDS and protein. In this range of n, rates of denaturation also depended on the choice of the acyl group as n increased to 7, in a manner compatible with favorable hydrophobic interactions between SDS and the −NHCOR groups. As n increased in the range 7 < n < 14, however, rates of denaturation stayed approximately constant; analysis suggested that these rates were compatible with an increasingly important contribution to denaturation that depended both on the net negative charge of the protein and on the hydrophobicity of the R group. The mechanism of denaturation thus seems to change with the extent of acylation of the protein. For derivatives with the same net electrostatic charge, rates of denaturation increased with the acyl group (by a factor of 3 for n 14) in the order CH3CONH− < CH3CH2CONH− < (CH3)2CHCONH− < CF3CONH−. These results suggested that the hydrophobicity of CF3CONH− is slightly greater (by a factor of <2) than that of RHCONH− with similar surface area.

Description

Other Available Sources

Keywords

Terms of Use

This article is made available under the terms and conditions applicable to Open Access Policy Articles (OAP), as set forth at Terms of Service

Endorsement

Review

Supplemented By

Referenced By

Related Stories