Figure 6. Determination of molecular mass by dynamic light scattering method of UV-A-unexposed and exposed WT αB-crystallin and its three deamidated mutants. A multiage laser light scattering instrument (Wyatt Technology, Santa Barbara, CA) coupled to a HPLC was used to determine the molecular mass of the WT protein and its deamidated mutant proteins. The figure shows elution profiles at 280 nm of UV-A-unexposed (^____) and UV-A exposed (-----) αB-Asn146Asp mutant protein from a TSK G-5000PW_XL column as well as the molecular mass. Similar to the UV-A-exposed αB-Asn146Asp mutant protein profile, a high molecular weight (HMW) protein peak that eluted first (at about 10 min) followed by a crystallin peak (at about 15 min) were also observed for WT αB-crystallin and the αB-Asn78Asp and αB-Asn78/146Asp mutant proteins.