Title : The
protein structure of recombinant human
lactoferrin produced in the milk of transgenic cows closely matches the structure of human milk-derived
lactoferrin
Abstract :
- Human lactoferrin ( hLF ) is an iron-binding glycoprotein involved in the host defence against infection and excessive inflammation
- As the availability of (human milk-derived) natural hLF is limited, alternative means of production of this biopharmaceutical are extensively researched
- Here we report the crystal structure of recombinant hLF ( rhLF ) expressed in the milk of transgenic cows at a resolution of 2.4 A. To our knowledge, the first reported structure of a recombinant protein produced in milk of transgenic livestock
- Even though rhLF contains oligomannose- and hybrid-type N-linked glycans next to complex-type glycans , which are the only glycans found on natural hLF , the structures are identical within the experimental error (r.m.s. deviation of only 0.28 A for the main- chain atoms)
- Of the differences in polymorphic amino acids between the natural and rhLF variant used, only the side- chain of Asp561 could be modeled into the rhLF electron density map
- Taken together, the results confirm the structural integrity of the rhLF variant used in this study
- It also confirms the validity of the transgenic cow mammary gland as a vehicle to produce recombinant human proteins