Dufe VT et al. (2005) FEBS Lett "Cloning, expression, characterisation and three-dimensional structure determination of Caenorhabditis elegans spermidine synthase."

Walter RD, Karlberg T, Dufe VT, Luersen K, Eschbach ML, Haider N, Al-Karadaghi S

[FEBS Lett, 2005]

The polyamine synthesis enzyme spermidine synthase (SPDS) has been cloned from the model nematode Caenorhabditis elegans. Biochemical characterisation of the recombinantly expressed protein revealed a high degree of similarity to other eukaryotic SPDS with the exception of a low affinity towards the substrate decarboxylated S-adenosylmethionine (K(m)=110muM) and a less pronounced feedback inhibition by the second reaction product 5''-methylthioadenosine (IC(50)=430muM). The C. elegans protein that carries a nematode-specific insertion of 27 amino acids close to its N-terminus was crystallized, leading to the first X-ray structure of a dimeric eukaryotic SPDS.