ζ-Crystallin is a major protein in the lens of Camelus dromedarius

Camel (Camelus dromedarius) lenses contain a protein with an apparent subunit M_r 38,000 that constitutes approximately 8-13% of the total protein. The protein has been purified and has a native M_r 140,000 as determined by gel filtration. This is consistent with its being a tetramer. The protein reacts with antibodies raised against both guinea pig ζ-crystallin and peptides corresponding to amino acids 1-10 and 295-308, but not to antibodies raised against amino acids 320-328 of ζ-crystallin. Based on these criteria it is concluded that this protein, which is a major constituent of camel lens, is ζ-crystallin. This may be the first example of a protein (enzyme) being independently utilized as a crystallin in the lens of species from two mammalian orders.