Protein and Peptide Letters - Volume 8, Issue 5, 2001

Structural studies of herpesvirus proteases establish that they belong to a new class of serine proteases and contain a novel Ser-His-His catalytic triad. Peptidomimetic inhibitors bind to the protease by forming an anti-parallel beeta-sheet with the enzyme. There are large conformational changes in the protease upon inhibitor binding, indicating that the protease is an induced-fit enzyme. Further studies are needed to und Read More

Ribonuclease A (RNase A) molecules have been adsorbed onto mica surfaces from aqueous solution at pH 7.4. Atomic force microscopy (AFM) images of native RNase A show aggregates of monomers each having a diameter of 9 nm. This is consistent with a globular unit the size of which would be substantially larger than that expected for a 13-kDa protein. These experiment suggest that the RNase A oligomer subunits exi Read More

Affinity chromatography using oligo DNA from a cis-active region (-453 / -389) of the human DSC2 promoter was used to isolate a protein from human CaCo-2 epithelial cells expressing DSC2. The protein was SDS-PAGE purified, trypsinized and analyzed by MALDI-TOF mass spectrometry. Peptide mass fingerprinting identified the protein as nucleolin, a ubiquitously expressed protein involved in gene regulation

The hydroxyapatite elution behavior of 3 fragments of human XPA (M98-F219 = XPA-MBD M59-F219 = XPA-EM M59-M273 = XPA-deltaN58) and full-length human XPA containing a 6-residue, N-terminal histidine tag (h6-XPA) are described. With increasing concentration of potassium phosphate the proteins elute in the order: XPA-EM, XPA-MBD, XPA-deltaN58, and h6-XPA. If hydroxyapatite affinity is related to DNA-binding affinity, Read More

Two major tRNA binding proteins were obtained by biochemical method from yeast crude extracts of total membrane proteins. They were further confirmed to be tRNA specific-binding proteins by gel mobility shift assay. N-terminal sequence assays showed that they were glyceraldehyde-3-phosphate dehydranase (GAPDH) and 3-phosphate glycerate kinase (PGK1), respectively.

The insecticidal neurotoxins AaIT, LqhIT2, and miew-agaIV from venom of Arachnida were rapidly re-purified from their respective crude venoms using mass spectrometry analyses and two high pressure chromatographic steps. The purity of each toxin was confirmed by capillary zone electrophoresis. Each toxin was identified by mass spectrometry and their biological activity confirmed by bioassays against tobacco cut Read More

Using a methodology based on HPLC fractionation, mass spectrometry analysis, and microinjection guide-bioassays, a peptide with toxicity to both insects and mammals was isolated from the venom of the scorpion Leiurus quinquestriatus hebraeus, and named LqhIV (after LqhII and LqhIII[1]). The primary sequence, circular dichroism spectrum and three-dimensional structure simulation of LqhIV indicate that it contains similar Read More

Negatively-charged phospholipid membrane does not affect the random coil conformation of a non-neurotoxic amyloid-beeta-peptide having a retro-sequence 35-25 (Abeta 35-25), whereas it changes the conformation of a neurotoxic normal-sequence peptide A beeta 25-35 from a random coil to a beeta-sheet-like structure under the same condition. The formation of the ordered structure seems to be closely related to the Read More

Structural properties of six closely related lectins isolated from plants belonging from the legume group Diocleinae were studied in solution. Affinity and gel filtration chromatography of the lectins at different pH conditions demonstrated that the lectins diverge in affinity for a specific matrix mainly at the pH range 4.0 up to 6.0 and that at neutral pH they tend to form dimers. Analysis of circular dichroism and fluorescence e Read More

Aldose reductase (AR) was cloned from the fungal pathogen, Magnaporthe grisea, expressed in Escherichia coli and purified to homogeneity. An experimental fungicide inhibits the M. grisea AR uncompetitively with respect to its aldehyde substrate with a Ki of 130 nM, the potency suggesting that AR is a biochemical target of the fungicide. The M. grisea AR has a high kcat and large differences in substrate specificities.

The human monoclonal antibody 2F5 is a potent neutralizer of most clades of HIV-1 and possesses protective effects against viral transmission. It recognizes the linear epitope ELDKWAS of the viral envelope protein gp41. As structural information about epitope recognition may help to develop an HIV-1 vaccine we initiated crystallographic analyses of mAb 2F5 and its epitope complex. We now report the preparation of the corre Read More

The basic-helix-loop-helix(bHLH) DNA binding domain of Aryl hydrocarbon receptor nucleus translocator (Arnt) was purified and crystallized in glutathione S transferase (GST) fusion form. The tetragonal crystal was grown in ammonium sulfate condition and diffracted up to 2.2 A.