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Adsorption and desorption of fibronectin (FN) were investigated at thin films of alternating maleic acid copolymers with octadecene (POMA) and with propene (PPMA). The results reveal that the interfacial mode of adsorbed FN depends on the predominant interactions and large amounts of FN were tightly bound to POMA by hydrophobic interactions whereas FN adsorbed on PPMA was concluded to attain an unfolded structure allowing for the electrostatic matching of positively charged residues on FN with the maleic acid groups.

Cells rapidly transduce forces exerted on extracellular matrix contacts into tyrosine kinase activation and recruitment of cytoskeletal proteins to reinforce integrincytoskeleton connections and initiate adhesion site formation. The relationship between these two processes has not been defined, particularly at the submicrometer level. Using talin1-deficient cells, it appears that talin1 is critical for building early mechanical linkages. Deletion of talin1 blocked laser tweezers, force-dependent reinforcement of submicrometer fibronectin-coated beads and early formation of adhesion sites in response to force, even though Src family kinases, focal adhesion kinase, and spreading were activated normally. Recruitment of vinculin and paxillin to sites of force application also required talin1. FilaminA had a secondary role in strengthening fibronectin--integrin--cytoskeleton connections and no role in stretch-dependent adhesion site assembly. Thus, force-dependent activation of tyrosine kinases is independent of early force-dependent structural changes that require talin1 as part of a critical scaffold.

The analysis helps in the identification of a gene, which can be used for the encoding of a modular xylase from Cellulosimicrobium sp. strain HY-13. The various different functional domains present in the xylase are also discussed.

The internalization ability of Lactococcus lactis internalin A (InI[A.sup.+]) and Lactococcus lactis producing either the fibronectin-binding protein A of Staphylococcus aureus (L. lactis FbBP[A.sup.+]) or its fibronectin binding domains C and D (L. lactis C[D.sup.+]) is compared. L. lactis FnBP[A.sup.+] and L. lactis FnBP[A.sup.+] has displayed comparable internalization rates in Caco-2 cells, while the internalization rate seen with L. lactis C[D.sup.+] is lower.