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Fabrics with antibacterial properties are of interest as medical textiles and also in hygiene applications where odor formation through bacterial activity has to be prevented. In this work Cu-containing lyocell fibers and fabric were prepared and characterized. Insertion of copper was obtained by treatment of cellulose fabrics with copper– d -gluconate complexes. The stable Cu(II)– d -gluconate complex was used to achieve controlled insertion of copper ions into the cellulose matrix. Secondly, the reduction of copper ions was achieved by use of sodium borohydride. Copper content in treated fabrics was determined by AAS; values ranged between 18.5 and 23.7 mmol Cu/kg cellulose. After five hand-washing cycles, 30% of the initial copper amount was left on the cellulose fabrics. Copper containing particles were identified with electron microscopy and by energy dispersive X-ray (EDX) analysis. The antibacterial properties of copper containing fabrics were tested against Staphylococcus aureus . Even with a rather low copper content (2.6 mmol Cu/kg cellulose fiber) 90% reduction of bacterial viability was achieved after 3 h of contact time.

β-Lactoglobulin (BLG) is a member of the lipocalin protein family and a major food-borne allergen in humans. Numerous in vitro studies have suggested a role for BLG in molecular transport processes; however, its physiological role remains enigmatic. A cellular receptor for BLG has been proposed, but has not yet been identified. Here we show that human LIMR, known to act as an endocytic receptor for lipocalin-1, also binds bovine BLG and mediates its cellular uptake. The specificity of this interaction is corroborated by a complete block of cellular uptake of BLG in the presence of LIMR antibodies or LIMR downregulation by antisense RNA. Furthermore, heterologous expression of human LIMR in insect cells mediates cellular internalization of FITC-BLG. Since LIMR is highly expressed in the human intestine, it might also function in the uptake of food-borne BLG.

Multiangle laser light scattering and fluorescence anisotropy decay measurements clarified the oligomeric states of native and recombinant tear lipocalin (lipocalin-1, TL). Native TL is monomeric. Recombinant TL (5-68 microM) with or without the histidine tag shows less than 7% dimer formation that is not in equilibrium with the monomeric form. Fluorescence anisotropy decay showed a correlation time of 9-10 ns for TL (10 microM-1 mM). Hydrodynamic calculations based on the crystallographic structure of a monomeric TL mutant closely concur with the observed correlation time. The solution properties calculated with HYDROPRO and SOLPRO programs from the available crystallographic structure of a monomeric TL mutant concur closely with the observed fluorescence anisotropy decay. The resulting model shows that protein topology is the major determinant of rotational correlation time and accounts for deviation from the Stokes-Einstein relation. The data challenge previous gel filtration studies to show that native TL exists predominantly as a monomer in solution rather than as a dimer. Delipidation of TL results in a formation of a complex oligomeric state (up to 25%). These findings are important as the dynamic processes in the tear film are limited by diffusional, translational as well as rotational, properties of the protein.