T-cell protein tyrosine phosphatase (TCPTP) exists as two forms generated by alternative splicing: a 48-kDa endoplasmic reticulum (ER)-associated form (TC48) and a 45-kDa nuclear form (TC45). To identify TCPTP substrates, we have generated substrate-trapping mutants, in which the invariant catalytic acid of TCPTP (D182) is mutated to alanine. The TCPTP D182A substrate-trapping mutants were tran...

Cellulose and hemicellulose account for a large portion of the world’s plant biomass. In nature, these polysaccharides are intertwined, forming complex materials that require multiple enzymes to degrade them. Multienzyme complexes (MECs) consist of a number of enzymes working in close proximity and synergistically to degrade complex substrates with higher efficiency than individual enzymes. The...

It is known that secondary transporters, which utilize transmembrane ionic gradients to drive their substrates up a concentration gradient, can reverse the uptake and instead release their substrates. Unfortunately, the Michaelis-Menten kinetic scheme, which is popular in transporter studies, does not include transporter reversal, and it completely neglects the possibility of equilibrium betwee...

Protein kinases play pivotal roles in numerous cellular functions; however, the specific substrates of each protein kinase have not been fully elucidated. We have developed a novel method called kinase-interacting substrate screening (KISS). Using this method, 356 phosphorylation sites of 140 proteins were identified as candidate substrates for Rho-associated kinase (Rho-kinase/ROCK2), includin...

The techniques that are presently available for the measurement of complex permittivities of dielectric substrates are only applicable to single layer substrates. This paper presents a new technique which uses the Finite Element Method (FEM) to estimate the complex permittivities of individual layers from the measurement of the S-parameters of a rectangular waveguide holding a multilayer dielec...

Commitment complexes contain U1 snRNP as well as pre-mRNA and are the earliest functional complexes that have been described during in vitro spliceosome assembly. We have used a gel retardation assay to analyze the role of the yeast pre-mRNA cis-acting sequences in commitment complex formation. The results suggest that only a proper 5' splice site sequence is required for efficient U1 snRNA-pre...

Abstract We employed N-benzyl-2-methyl-4-nitroaniline (BNA) crystals bonded on substrates of different thermal conductivity to generate THz radiation by pumping with 800 nm laser pulses. Crystals sapphire substrate provided four times more yield than glass substrate. A pyrodetector and a single-shot electro-optic (EO) diagnostic were for measuring the energy temporal characterisation pulse. Sys...

In plasma membranes of human neutrophils, we identified two major pertussis toxin substrates of 40 kDa Mr with pI values of 5.30 and 5.37. Only the acidic of the two substrates was also present in neutrophil cytosol. Two-dimensional tryptic peptide maps revealed a high degree of homology of cytosolic and particulate substrates. Purified G-protein beta gamma-complex stimulated pertussis toxin-ca...

The purified multienzyme complex fatty acid synthetase from yeast synthesizes palmitoyland stearoyl-CoA with NADPH, ace@-CoA and malonylCoA as substrates. At least seven different enzymatic steps have been shown to occur in the overall synthesis by the use of appropriate model substrates [l] , .e.g. S-acetoacetyl-N-acetylcysteamine for the @-ketoreductase partial activity. As reported in this c...