International Journal of Peptide and Protein Research, 2009
Several toxins with distinct pharmacological properties were isolated from the venom of Thailand ... more Several toxins with distinct pharmacological properties were isolated from the venom of Thailand cobra (Naja naja siamensis) by cation‐exchange chromatography. Two neurotoxins and one basic toxin with cardiotoxic activity were further purified and sequenced. The neurotoxins characterized were closely similar to the previously reported long‐ and short‐chain neutrotoxins. The complete sequences of one minor neurotoxin and one cardiotoxin analogue were determined with the automatic protein sequencer in non‐stop single runs of Edman degradation coupled with C‐terminal sequence determination with carboxypeptidase digestion. The minor neurotoxin consists of 62 amino‐acid residues with 8 cysteine residues and is found to be almost identical to cobrotoxin, a major toxic component of Formosa cobra (Naja naja atra). The sequence comparison of the 60‐residue cardiotoxin with other reported cytotoxins of snake venoms indicates that 8 cysteine residues at the positions 3, 14, 21, 38, 42, 53, 54,...
International journal of peptide and protein research, 1988
gamma-Crystallins were isolated from the homogenate of frog eye lenses (Rana catesbeiana) by excl... more gamma-Crystallins were isolated from the homogenate of frog eye lenses (Rana catesbeiana) by exclusion gel chromatography and further purified by cation-exchange chromatography. They were the only group of crystallins possessing free amino groups amenable to sequence analysis by Edman degradation. Comparison of the amino acid contents of the purified subfractions of gamma-crystallins indicated their close relatedness in amino acid compositions and probably sequence homology as well. The amino-terminal sequence analysis of the purified gamma-crystallin subfractions showed extensive homology between these amphibian gamma-crystallin polypeptides themselves and also those from other vertebrate species, suggesting the existence of a multigene family and their close relatedness to gamma-crystallins of other vertebrates. The sequence comparison of the gamma-crystallin polypeptides from all major classes of vertebrates has provided strong support for the divergent evolution of gamma-crystal...
A detailed hydrodynamic study has been made on the γ-crystallin of the bovine lens. Sedimentation... more A detailed hydrodynamic study has been made on the γ-crystallin of the bovine lens. Sedimentation study indicates that γ-crystallin shows a nearly gaussian peak throughout the course of sedimentation at high speed, using a synthetic boundary cell. The diffusion and sedimentation coefficients are 10.3×10−7 cm2/sec and 2.51 S, respectively. The weight-average molecular weight of the unfractionated γ-crystallin calculated from sedimentation
Lens crystalline were isolated from homogenates of reptilian eye lenses (Caiman crocodylus apapor... more Lens crystalline were isolated from homogenates of reptilian eye lenses (Caiman crocodylus apaporiensis) by gel‐permeation chromatography and characterized by gel electrophoresis, and amino acid and N‐terminal sequence analyses. Four fractions corresponding to α‐, δ/ε/β/‐, β‐ and γ‐crystallins were identified on the basis of their electrophoretic patterns as revealed by SDS gel electrophoresis. Comparison of the amino acid contents of reptilian crystallins with those of mammals suggests that each orthologous class of crystallins from the evolutionarily distant species still exhibits similarity in their amino acid compositions and probably sequence homology as well. All fractions except that of γ‐crystallin were found to be N‐terminally blocked. N‐terminal sequence analysis of the purified γ‐crystallin subfractions showed extensive homology between the reptilian γ‐crystallin polypeptides themselves and also those from other vertebrate species, suggesting the existence of a multigene ...
Lens crystallins were isolated from the homogenates of mammalian eye lenses derived from three di... more Lens crystallins were isolated from the homogenates of mammalian eye lenses derived from three different species by gel permeation chromatography and characterized by SDS-gel electrophoresis, isoelectric focusing, amino acid analysis and N-terminal sequence analysis. Five fractions corresponding to HM alpha-, alpha-, beta H-, beta L- and gamma-crystallins were obtained for the crystallins from these phylogenetically distant species. The native molecular masses for these purified fractions and their polypeptide compositions were determined by gel filtration and SDS-gel electrophoresis respectively, revealing the typical subunit compositions for each classified crystallin. The gel pattern of gamma-crystallins from the marmot lens appeared to be more complex than those of gibbon and deer lenses. Comparison of the amino acid contents of each orthologous class of mammalian crystallins with those of evolutionarily distant species still exhibited similarity in their amino acid compositions. The charge heterogeneity of each crystallin fraction can be detected by isoelectric focusing under denaturing conditions. N-terminal sequence analysis of the crystallin fractions revealed that all fractions except that of gamma-crystallin are N-terminally blocked. Extensive sequence similarity between mammalian gamma-crystallin polypeptides were found, which suggested the close relatedness of gamma-crystallins amongst different species of mammals and also established the heterogeneous nature of this multigene family.
Chuacterization of lens crystallins from black swan, a rare aquatic bird belonging to the family ... more Chuacterization of lens crystallins from black swan, a rare aquatic bird belonging to the family Anatidae, was carried out to search for e-crystallin with lactate dehydrogenase activity. Biochemical comparison of E-crystallins isolated from the swan and duck lenses plus lactate dehydrogenase of chicken heart has also been made in order to establish the structural/functional relatedness of these proteins. Amino acid analyses showed essentially similar overall compositions for these three proteins. Kinetic analysis revealed differences between avian E-crystallins and the authentic heart-type lactate dehydrogenase. The swan lenses similar to duck lenses appeared to contain a thermostable E-crystallin which possesses very high enzymatic activity of lactate dehydrogenase. The characterization of E-crystallins from the available species of aquatic birds may provide some insights into the evolution of this unique crystallin in the Aves and their enzymatic roles inside the lens.
Colony-forming ability was employed in evaluating the susceptibility to in vitro gamma ionizing r... more Colony-forming ability was employed in evaluating the susceptibility to in vitro gamma ionizing radiation in human diploid skin fibroblasts (HDF). Twelve pairs of HDF, each composed of fibroblasts from excised keloid lesion and local normal skin tissue as its control, were studied in patients with clinically persistent keloids. Parameters of radiosensitivity, both D0 and D10, and growth kinetics were examined. The radiosensitivity in three of the 12 keloids (25%) were demonstrated significantly increased than their counterpart controls, even though no difference in growth kinetics in between. Moreover, a broad range in the radiosensitivity of fibroblast cells was demonstrated and it is suggested that there is a great heterogeneity of cellular response to radiation in HDF.
International Journal of Peptide and Protein Research, 2009
Several toxins with distinct pharmacological properties were isolated from the venom of Thailand ... more Several toxins with distinct pharmacological properties were isolated from the venom of Thailand cobra (Naja naja siamensis) by cation‐exchange chromatography. Two neurotoxins and one basic toxin with cardiotoxic activity were further purified and sequenced. The neurotoxins characterized were closely similar to the previously reported long‐ and short‐chain neutrotoxins. The complete sequences of one minor neurotoxin and one cardiotoxin analogue were determined with the automatic protein sequencer in non‐stop single runs of Edman degradation coupled with C‐terminal sequence determination with carboxypeptidase digestion. The minor neurotoxin consists of 62 amino‐acid residues with 8 cysteine residues and is found to be almost identical to cobrotoxin, a major toxic component of Formosa cobra (Naja naja atra). The sequence comparison of the 60‐residue cardiotoxin with other reported cytotoxins of snake venoms indicates that 8 cysteine residues at the positions 3, 14, 21, 38, 42, 53, 54,...
International journal of peptide and protein research, 1988
gamma-Crystallins were isolated from the homogenate of frog eye lenses (Rana catesbeiana) by excl... more gamma-Crystallins were isolated from the homogenate of frog eye lenses (Rana catesbeiana) by exclusion gel chromatography and further purified by cation-exchange chromatography. They were the only group of crystallins possessing free amino groups amenable to sequence analysis by Edman degradation. Comparison of the amino acid contents of the purified subfractions of gamma-crystallins indicated their close relatedness in amino acid compositions and probably sequence homology as well. The amino-terminal sequence analysis of the purified gamma-crystallin subfractions showed extensive homology between these amphibian gamma-crystallin polypeptides themselves and also those from other vertebrate species, suggesting the existence of a multigene family and their close relatedness to gamma-crystallins of other vertebrates. The sequence comparison of the gamma-crystallin polypeptides from all major classes of vertebrates has provided strong support for the divergent evolution of gamma-crystal...
A detailed hydrodynamic study has been made on the γ-crystallin of the bovine lens. Sedimentation... more A detailed hydrodynamic study has been made on the γ-crystallin of the bovine lens. Sedimentation study indicates that γ-crystallin shows a nearly gaussian peak throughout the course of sedimentation at high speed, using a synthetic boundary cell. The diffusion and sedimentation coefficients are 10.3×10−7 cm2/sec and 2.51 S, respectively. The weight-average molecular weight of the unfractionated γ-crystallin calculated from sedimentation
Lens crystalline were isolated from homogenates of reptilian eye lenses (Caiman crocodylus apapor... more Lens crystalline were isolated from homogenates of reptilian eye lenses (Caiman crocodylus apaporiensis) by gel‐permeation chromatography and characterized by gel electrophoresis, and amino acid and N‐terminal sequence analyses. Four fractions corresponding to α‐, δ/ε/β/‐, β‐ and γ‐crystallins were identified on the basis of their electrophoretic patterns as revealed by SDS gel electrophoresis. Comparison of the amino acid contents of reptilian crystallins with those of mammals suggests that each orthologous class of crystallins from the evolutionarily distant species still exhibits similarity in their amino acid compositions and probably sequence homology as well. All fractions except that of γ‐crystallin were found to be N‐terminally blocked. N‐terminal sequence analysis of the purified γ‐crystallin subfractions showed extensive homology between the reptilian γ‐crystallin polypeptides themselves and also those from other vertebrate species, suggesting the existence of a multigene ...
Lens crystallins were isolated from the homogenates of mammalian eye lenses derived from three di... more Lens crystallins were isolated from the homogenates of mammalian eye lenses derived from three different species by gel permeation chromatography and characterized by SDS-gel electrophoresis, isoelectric focusing, amino acid analysis and N-terminal sequence analysis. Five fractions corresponding to HM alpha-, alpha-, beta H-, beta L- and gamma-crystallins were obtained for the crystallins from these phylogenetically distant species. The native molecular masses for these purified fractions and their polypeptide compositions were determined by gel filtration and SDS-gel electrophoresis respectively, revealing the typical subunit compositions for each classified crystallin. The gel pattern of gamma-crystallins from the marmot lens appeared to be more complex than those of gibbon and deer lenses. Comparison of the amino acid contents of each orthologous class of mammalian crystallins with those of evolutionarily distant species still exhibited similarity in their amino acid compositions. The charge heterogeneity of each crystallin fraction can be detected by isoelectric focusing under denaturing conditions. N-terminal sequence analysis of the crystallin fractions revealed that all fractions except that of gamma-crystallin are N-terminally blocked. Extensive sequence similarity between mammalian gamma-crystallin polypeptides were found, which suggested the close relatedness of gamma-crystallins amongst different species of mammals and also established the heterogeneous nature of this multigene family.
Chuacterization of lens crystallins from black swan, a rare aquatic bird belonging to the family ... more Chuacterization of lens crystallins from black swan, a rare aquatic bird belonging to the family Anatidae, was carried out to search for e-crystallin with lactate dehydrogenase activity. Biochemical comparison of E-crystallins isolated from the swan and duck lenses plus lactate dehydrogenase of chicken heart has also been made in order to establish the structural/functional relatedness of these proteins. Amino acid analyses showed essentially similar overall compositions for these three proteins. Kinetic analysis revealed differences between avian E-crystallins and the authentic heart-type lactate dehydrogenase. The swan lenses similar to duck lenses appeared to contain a thermostable E-crystallin which possesses very high enzymatic activity of lactate dehydrogenase. The characterization of E-crystallins from the available species of aquatic birds may provide some insights into the evolution of this unique crystallin in the Aves and their enzymatic roles inside the lens.
Colony-forming ability was employed in evaluating the susceptibility to in vitro gamma ionizing r... more Colony-forming ability was employed in evaluating the susceptibility to in vitro gamma ionizing radiation in human diploid skin fibroblasts (HDF). Twelve pairs of HDF, each composed of fibroblasts from excised keloid lesion and local normal skin tissue as its control, were studied in patients with clinically persistent keloids. Parameters of radiosensitivity, both D0 and D10, and growth kinetics were examined. The radiosensitivity in three of the 12 keloids (25%) were demonstrated significantly increased than their counterpart controls, even though no difference in growth kinetics in between. Moreover, a broad range in the radiosensitivity of fibroblast cells was demonstrated and it is suggested that there is a great heterogeneity of cellular response to radiation in HDF.
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