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E Sulkowski

Publications and source records attributed to E Sulkowski.

At least 55 records · Page 3Linked to original sources
PubMed1975

Molecular structure of human fibroblast and leukocyte interferons: probe by lectin and hydrophobic chromatography.

Structural differences between human leukocyte virus-induced interferon and human fibroblast polyinosinic-polycytidylic acid (rIn-rCn)-induced interferon have been noted in previous studies. This study reports the behavior of human leukocyte and fibroblast interferon, induced by virus and by rIn-rCn, in several lectin and hydrophobic chromatographic systems. Differences in both glycosylation and in hydrophobicity of human leukocyte and fibroblast interferons are documented. Human fibroblast interferon is a glycoprotein, whereas our evidence suggests that human leukocyte interferon probably is not. Also, fibroblast interferon is more hydrophobic than leukocyte interferon, as probed on several hydrophobic adsorbents. The possible relationships of these differences to each other and to antigenic variations are discussed. Generally, the differences appear to be attributable to the cell type in which the interferon was induced. However, our results suggest that at least subtle differences in the processing of the induction signal (virus or rIn-rCn) within the same cell type may occur, slightly altering some structural features.

Chromatography↗
PubMedDate not supplied

Immobilized metal-ion affinity chromatography: imidazole proton pump and chromatographic sequelae. I. Proton pump.

Complexation of imidazole (Im) with an iminodiacetate (IDA) metal chelate [IDA-M(II)] ligand of chelating gel results in an acidification of the mobile phase. The scope of the action of this IDA-M(II)Im 'proton pump' in IMAC is determined by: (a) IDA-M(II) density of the gel; (b) concentration of applied Im; and (c) the buffering capacity of the mobile phase. Application of Im onto a metal chelate column in a gradient rather than in a stepwise manner, mitigates the proton pump's action, as it does an increase of buffer concentration in the mobile phase. However, only an antecedent conversion of the metal chelate gel, IDA-M(II), to its Im derivative, IDA-M(II) Im, can effectively circumscribe the action of the proton pump. The same holds true, as anticipated, when another chelating ligand (nitrilotriacetate) is used.

Buffers↗
PubMedDate not supplied

Immobilized metal-ion affinity chromatography: imidazole proton pump and chromatographic sequelae. II. Chromatographic sequelae.

Isocratic elution with imidazole of some protein models from a chelating gel, CSFF-IDA-M(II), resulted in their desorption owing to the low pH(6-->4) of the mobile, phase rather than to the imidazole itself (imidazole-generated fall in pH; proton pump). Gradient elution with imidazole was best accomplished when the chelating gel was initially converted into its imidazole complex, CSFF-IDA-M(II)Im. The exploitation of the imidazole-generated proton pump in the IMAC of proteins may enhance the versatility of this type of chromatography.

Animals↗