Abstact

The C-terminal Kunitz-type domain from the alpha3 chain of human type VI collagen (C5), a single amino-acid residue chain with three disulfide bridges, was refined at 0.9 A resolution in a monoclinic form, space group P2(1) with one molecule per asymmetric unit, using data collected at cryogenic temperature (110 K). The average protein factor decreases from 21 A(2) at room temperature (RT) to 12 A(2) at cryotemperature (100 K, CT). The spatially close N- and C-termini remain highly disordered. The different structural motifs of C5 were analyzed in terms of rigid-body displacement (TLS analyses) and show dominant libration motion for the secondary structure.