Publications

• Biosynthesis of long-chain polyamines by crenarchaeal polyamine synthases from Hyperthermus butylicus and Pyrobaculum aerophilum.

  Knott J.M.

  Polyamines are ubiquitously present in all organisms. In addition to the common polyamines, thermophilic archaea synthesize long-chain polyamines. In the present study polyamine synthases from Hyperthermus butylicus and Pyrobaculum aerophilum were cloned and their substrate specificity was analyze ... >> More

  Polyamines are ubiquitously present in all organisms. In addition to the common polyamines, thermophilic archaea synthesize long-chain polyamines. In the present study polyamine synthases from Hyperthermus butylicus and Pyrobaculum aerophilum were cloned and their substrate specificity was analyzed. The polyamine synthase HbSpeE II from H. butylicus synthesized long-chain polyamines with high activity using the same mechanism that is used by a wide range of organisms to synthesize common polyamines, in which the aminopropyl residue derives from decarboxylated S-adenosylmethionine. This is the first polyamine synthase described that synthesizes a polyamine longer than a tetramine with high activity. << Less

  FEBS Lett. 583:3519-3524(2009) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.

• Purification and characterization of propylamine transferase from Sulfolobus solfataricus, an extreme thermophilic archaebacterium.

  Cacciapuoti G., Porcelli M., Carteni-Farina M., Gambacorta A., Zappia V.

  The enzyme propylamine transferase, catalyzing the transfer of the propylamine moiety from S-adenosyl(5')-3-methylthiopropylamine to several amine acceptors, has been purified 643-fold in 20% yield from Sulfolobus solfataricus, an extreme thermophilic archaebacterium optimally growing at 87 degree ... >> More

  The enzyme propylamine transferase, catalyzing the transfer of the propylamine moiety from S-adenosyl(5')-3-methylthiopropylamine to several amine acceptors, has been purified 643-fold in 20% yield from Sulfolobus solfataricus, an extreme thermophilic archaebacterium optimally growing at 87 degrees C. The purified enzyme (specific activity 2.05 units/mg protein), is homogeneous by criteria of gel electrophoresis, gel filtration, isoelectric focusing and ultracentrifugation analysis. The molecular mass of the native enzyme was estimated to be about 110 kDa by gel permeation and ultracentrifugation analysis. The protein migrates on SDS/polyacrylamide gel electrophoresis as a single band of 35 kDa, suggesting that the enzyme is a trimer composed by identical subunits. An optimum pH of 7.5 and an acidic isoelectric point of 5.3 have been calculated. The optimum temperature was 90 degrees C and no loss of activity is observable even after exposure of the purified enzyme to 100 degrees C for 1 h. No reducing agents are required for enzymatic activity. Substrate specificity towards the amine acceptors is rather broad in that 1,3-diaminopropane (Km = 1675 microM), putrescine (Km = 3850 microM), sym-norspermidine (Km = 954 microM) and spermidine (Km = 1539 microM) are recognized as substrates. Conversely S-adenosyl(5')-3-methylthiopropylamine is the only propylamine donor (Km = 7.9 microM) and the deamination of the sulfonium compound prevents the recognition by the enzyme. The reaction is irreversible and initial-rate kinetic studies indicate that the propylamine transfer is operated through a sequential mechanism. 5'-Methylthioadenosine, a product of the reaction, acts as a powerful competitive inhibitor with a Ki of 3.7 microM. Enzyme-substrate binding sites have been investigated with the aid of several substrate analogs and products. Among the compounds assayed, 5'-methylthiotubercidin, S-adenosyl(5')-3-thiopropylamine and S-adenosyl-3-thio-1,8-diaminooctane are the most active inhibitors. << Less

  Eur. J. Biochem. 161:263-271(1986) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.