Ruth M. Starzyk

Inhibition of leukocyte-endothelial cell interactions and inflammation by peptides from a bacterial adhesin which mimic coagulation factor X.

Factor X (factor ten) of the coagulation cascade binds to the integrin CD11b/CD18 during inflammation, initiating procoagulant activity on the surface of leukocytes (Altieri, D.C., O.R. Etingin, D.S. Fair, T.K. Brunk, J.E. Geltosky, D.P. Hajjar, and T. S. Edgington. 1991. Science [Wash.DC]. 254:1200-1202). Filamentous hemagglutinin (FHA), an adhesin of Bordetella pertussis also binds to the CD11b/CD18 integrin (Relman D., E. Tuomanen, S. Falkow, D.T. Golenbock, K. Saukkonen, and S.D. Wright. 1990. Cell. 61:1375-1382). FHA and the CD11b/CD18 binding loops of Factor X share amino acid sequence similarity. FHA peptides similar to Factor X binding loops inhibited 125I-Factor X binding to human neutrophils and prolonged clotting time. In addition, ETKEVDG and its Factor X analogue prevented transendothelial migration of leukocytes in vitro and reduced leukocytosis and blood brain barrier disruption in vivo. Interference with leukocyte migration by a coagulation-based peptide suggests a novel strategy for antiinflammatory therapy.

RNA and DNA sequence recognition and structure-function of aminoacyl tRNA synthetases

Abstract Aminoacyl tRNA sythesases establish the rules of the genetic code through specific protein-RNA interactions which may have a covalent component. Structural features of these enzymes are now emerging and recently it was discovered that genes can be regulated through synthetase-DNA interactions.