In classical interferometric null test measurements, the measurement and reference beam path should be the same. A difference in the beam paths results in the so called retrace error. One very common approach to avoid retrace errors is to adapt the measurement wavefront to the reference wavefront with a computer generated hologram (CGH), which is costly and time consuming.
View Article and Find Full Text PDFInterferometric determination of sphere radii is a well known technique. To keep accuracy high and uncertainties low, a precisely controlled environment is usually necessary. Environmental changes in temperature lead to time dependent drift in important measurement parameters and to disturbed results.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 1998
Tyrosylprotein sulfotransferase (TPST) is a 54- to 50-kDa integral membrane glycoprotein of the trans-Golgi network found in essentially all tissues investigated, catalyzing the tyrosine O-sulfation of soluble and membrane proteins passing through this compartment. Here we describe (i) an approach to identify the TPST protein, referred to as MSC (modification after substrate crosslinking) labeling, which is based on the crosslinking of a substrate peptide to TPST followed by intramolecular [35S]sulfate transfer from the cosubstrate 3'-phosphoadenosine 5'-phosphosulfate (PAPS); and (ii) the molecular characterization of a human TPST, referred to as TPST-2, whose sequence is distinct from that reported [TPST-1; Ouyang, Y.-B.
View Article and Find Full Text PDFSulfation is the most abundant post-translational modification of tyrosine residues and occurs in many soluble and membrane proteins passing through the secretory pathway of metazoan cells. The sulfation reaction is catalysed by tyrosylprotein sulfotransferase, a membrane-bound enzyme of the trans-Golgi-network. Tyrosylprotein sulfotransferase has been purified and its substrate specificity characterized.
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