(a) Amino acid sequences of N-PEGylated protein 6PEG-F,T and its derivatives. N = Asn- PEG (see Figure 1, panel b for PEG structure). (b) Variable temperature CD data for protein 6-F,T, glycoprotein 6g-F,T (ref. 26), and N-PEGylated protein 6PEG-F,T at a protein concentration of 10 μM in 20 mM sodium phosphate buffer (pH 7). Data are shown for each of three replicate experiments on each protein. (c) Triple mutant cycle cube formed by proteins 6-F,T, and 6PEG-F,T, and their derivatives.