Glycoprotein-surfactant interactions: A calorimetric and spectroscopic investigation of the phytase-SDS system

Abstract

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Hydrophobization of bovine serum albumin with cationic surfactants with different hydrophobic chain length

“…The majority of the works published in this field deal with the nature of the interaction of these proteins with anionic surfactants, whereas the number of publications addressing the effect of cationic and non-ionic surfactants on various proteins is much lower [24]. The most extensively studied anionic surfactants are sodium dodecyl sulfate (SDS) [25][26][27][28][29][30][31][32][33] and sodium alkyl sulfates with various carbon chain lengths. Research by Lu et al revealed that the interaction between surfactant and protein is only slightly affected by the nature of the polar part of the surfactant and much more by the length of the apolar carbon chain [34].…”

Stability, denaturation and refolding of Mycobacterium tuberculosis MfpA, a DNA mimicking protein that confers antibiotic resistance

“…6). When SDS denaturation occurs at concentrations below the critical micelle concentration, protein oligomer dissociation rather than subunit denaturation is typically observed [26, 29]. The relatively small numbers of SDS molecules that bind to MfpA as well as the changes in the spectral measures are consistent with this view.…”

“…3B & 5A). The two negative peaks at ~ 206 nm and 222 nm are characteristic of proteins in SDS [26, 27], that typical of α/β proteins [21] and completely different from that of the native MfpA [4, 6]. The fluorescence emission λ max red shifts to ~ 342 nm indicating increased exposure of the Trp residues, again recapitulating urea refolded MfpA (Fig.…”

Microbiotechnology Based Surfactants and Their Applications

“…The low binding number may however be due to a combination of several disulfide bonds and the heavy glycosylation of the linker. Glycosylation has previously been shown to decrease the amount of SDS which binds to enzymes (Bagger et al, 2007). In contrast to SDS, CZ titrations with RL overlapped with RL titrations into buffer ( Figure 9D).…”

“…ITC provides valuable information about the thermodynamics and stoichiometry of binding as shown in several studies (Nielsen et al, 2005(Nielsen et al, , 2007Bagger et al, 2007;Andersen et al, 2008Otzen et al, 2009). Different protein concentrations of the three enzymes were therefore subjected to titrations with SDS and RL and the recorded heat flow was accordingly analyzed.…”