The simian virus 40 large T antigen (T antigen) inactivates tumor suppressor proteins and therefore has been used in numerous studies to probe the mechanisms that control cellular growth and to generate immortalized cell lines. Binding of T antigen to the Rb family of growth-regulatory proteins is necessary but not sufficient to cause transformation. The molecular mechanism underlying T-antigen...

The human immunodeficiency virus (HIV-1) infects T lymphocytes via an interaction between the virus envelope glycoprotein gp120 and the CD4 antigen of T helper cells. Previous studies demonstrated that mutations in various regions of CD4 domain 1 lead to the loss of gp120 binding. In the present study the gp120 binding site was constructed in rat CD4 by replacing rat with human CD4 sequence. A ...

The bovine papillomavirus replication initiator protein E1 is an origin of replication (ori)-binding protein absolutely required for viral DNA replication. In the presence of the viral transcription factor E2, E1 binds to the ori and initiates DNA replication. To understand how the E1 initiator recognizes the ori and how E2 assists in this process, we have expressed and purified a 166-amino-aci...

N-acetyllactosamine is the most prevalent disaccharide moiety in the glycans on the surface of mammalian cells and often found as repeat units in the linear and branched polylactosamines, known as i- and I-antigen, respectively. The β1-4-galactosyltransferase-I (β4Gal-T1) enzyme is responsible for the synthesis of the N-acetyllactosamine moiety. To understand its oligosaccharide acceptor specif...

The thymus leukemia antigen (TLA) is a class Ib, or 'nonclassical' class I molecule, one of several encoded within the Tla locus of the mouse major histocompatibility complex (MHC). It structurally resembles the H-2K, D, and L class I transplantation antigens, which present processed peptides to cytotoxic T lymphocytes (CTLs). Although their function(s) are unknown, there has been recent specul...

The migration of antigen-specific T cells to nonlymphoid tissues is thought to be important for the elimination of foreign antigens from the body. However, recent results showing the migration of activated T cells into many nonlymphoid tissues raised the possibility that antigen-specific T cells do not migrate preferentially to nonlymphoid tissues containing antigen. We addressed this question ...

Computational analysis, design and expression of hybrid antibody in Single Chain Fragment Variable (scFv) form for identifying surface antigen factor H binding protein (fHbp) Neisseria meningitidis

Protein function may be modulated by an event occurring far away from the functional site, a phenomenon termed allostery. While classically allostery involves conformational changes, we recently observed that charge redistribution within antibody can also lead to allosteric effect, modulating kinetics of binding target antigen. In present work, study association polyhistidine tagged enzyme (pho...