ArticlePlant molecular biology2007
Putrescine N-methyltransferases--a structure-function analysis.
Article in Plant molecular biology, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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Who cites it
16 citing papers in PubMed, 59 citations in OpenAlex.
- Chitosan nanoparticles as a strategy for enhancing h6h gene expression and tropane alkaloid production in Hyoscyamus reticulatus hairy roots.Scientific reports · 2025Article
- Functional Diversification and Structural Origins of Plant Natural Product Methyltransferases.Molecules (Basel, Switzerland) · 2022Review
- Erythroxylum in Focus: An Interdisciplinary Review of an Overlooked Genus.Molecules (Basel, Switzerland) · 2019Review
- Tropane Alkaloids: Chemistry, Pharmacology, Biosynthesis and Production.Molecules (Basel, Switzerland) · 2019Review
- Rootstock-induced molecular responses associated with drought tolerance in sweet orange as revealed by RNA-Seq.BMC genomics · 2019Article
- Molecular Origins of Functional Diversity in Benzylisoquinoline Alkaloid Methyltransferases.Frontiers in plant science · 2019Review
- Conservation of Thermospermine Synthase Activity in Vascular and Non-vascular Plants.Frontiers in plant science · 2019Article
- The impact of genome evolution on the allotetraploid Nicotiana rustica - an intriguing story of enhanced alkaloid production.BMC genomics · 2018Article
- Fission Yeast srm1 is Involved in Stress Response and Cell Cycle.Current microbiology · 2017Article
- Article
- Evolution of the key alkaloid enzyme putrescine N-methyltransferase from spermidine synthase.Frontiers in plant science · 2013Article
- Lysine decarboxylase catalyzes the first step of quinolizidine alkaloid biosynthesis and coevolved with alkaloid production in leguminosae.The Plant cell · 2012Article
- From amino acid to glucosinolate biosynthesis: protein sequence changes in the evolution of methylthioalkylmalate synthase in Arabidopsis.The Plant cell · 2011Article
- Review
- Purification, crystallization and X-ray diffraction analysis of pavine N-methyltransferase from Thalictrum flavum.Acta crystallographica. Section F, Structural biology and crystallization communications · 2008Article
- Role of Polyamines in Mitigating Salinity Stress in Ornamental and Food Crops.Physiologia plantarumReview
Corrections and comments
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Authors and funding
7 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Putrescine N-methyltransferase (PMT) is a key enzyme of plant secondary metabolism at the start of the specific biosynthesis of nicotine, of tropane alkaloids, and of calystegines that are glycosidase inhibitors with nortropane structure. PMT is assumed to have developed from spermidine synthases (SPDS) participating in ubiquitous polyamine metabolism. In this study decisive differences between both enzyme families are elucidated. PMT sequences were known from four Solanaceae genera only, therefore additional eight PMT cDNA sequences were cloned from five Solanaceae and a Convolvulaceae. The encoded polypeptides displayed between 76% and 97% identity and typical amino acids different from plant spermidine synthase protein sequences. Heterologous expression of all enzymes proved catalytic activity exclusively as PMT and K (cat) values between 0.16 s(-1) and 0.39 s(-1). The active site of PMT was initially inferred from a protein structure of spermidine synthase obtained by protein crystallisation. Those amino acids of the active site that were continuously different between PMTs and SPDS were mutated in one of the PMT sequences with the idea of changing PMT activity into spermidine synthase. Mutagenesis of active site residues unexpectedly resulted in a complete loss of catalytic activity. A protein model of PMT was based on the crystal structure of SPDS and suggests that overall protein folds are comparable. The respective cosubstrates S-adenosylmethionine and decarboxylated S-adenosylmethionine, however, appear to bind differentially to the active sites of both enzymes, and the substrate putrescine adopts a different position.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.