Polypeptide elongation factor Tu from Halobacterium marismortui.

F Guinet; R Frank; R Leberman

doi:10.1111/j.1432-1033.1988.tb13943.x

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Polypeptide elongation factor Tu from Halobacterium marismortui.

F Guinet·R Frank·R Leberman

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Abstract

A GDP-binding protein of 60 kDa from Halobacterium marismortui has been purified to homogeneity. The purification has been carried out in high-salt buffers or in 50% glycerol buffers to protect the halophilic protein from denaturation. Evidence that this protein is the halophilic elongation factor Tu (hEF-Tu) is provided by the high homology of its N terminus with the corresponding sequences of other EF-Tus, and by immunological studies. Like some other EF-Tus the native protein can be cleaved with trypsin without concomitant loss of GDP-binding ability. The molecular mass of this hEF-Tu is higher than that for the corresponding factors from other sources including the halobacterium Halobacterium cutirubrum. The protein possesses typical halophilic characteristics, in that it is stable and active in 3 M KCl or 2 M (NH4)2SO4. Some other properties, like autofragmentation under sample treatment before SDS-PAGE, are described.

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Amino Acid Sequence Amino Acids Electrophoresis, Polyacrylamide Gel GTP-Binding Proteins Halobacterium Peptide Elongation Factor Tu Protein Denaturation Journal Article

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F Guinet, R Frank, R Leberman. 1988-03-15. Polypeptide elongation factor Tu from Halobacterium marismortui.. https://doi.org/10.1111/j.1432-1033.1988.tb13943.x

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