Description: Das Projekt "From Amino Acid to Glucosinolate Biosynthesis: Protein Sequence Changes in the Evolution of Methylthioalkylmalate Synthase in Arabidopsis" wird/wurde ausgeführt durch: Max-Planck-Institut für chemische Ökologie.In the evolutionary arms race, small changes can be sufficient to gain a crucial advantage over the enemy. Scientists at the Max Planck Institute for Chemical Ecology found out recently that the ancestor of a gene involved in making chemical defenses in plants of the mustard family (Brassicaceae), such as rapeseed and cabbage, originally had a completely different function, playing a part in the formation of leucine, an essential amino acid for humans. Only small changes in the structure of the enzyme enabled it to take over completely new tasks that could, as shown in this study, increase the survival advantage of the plants. Plants are continually exposed to herbivore attack. To defend themselves, they have developed sophisticated chemical defense mechanisms. Plants of the mustard family, such as thale cress (Arabidopsis thaliana), produce glucosinolates (mustard oil glucosides) to protect themselves against herbivory. Scientists know many different kinds of these molecules; they have a similar structure, but different side chains. If insect larvae feed on mustard plants, glucosinolates are hydrolyzed to form toxic isothiocyanates. Chemists call this the 'mustard oil bomb'. Special enzymes are responsible for catalyzing the synthesis of different side chains of the various glucosinolates. Scientists at the Max Planck Institute for Chemical Ecology in Jena have now isolated one of these enzymes from Arabidopsis thaliana and discovered a surprising new insight. Jan-Willem de Kraker and Jonathan Gershenzon reported that the enzyme methylthioalkylmalate synthase (MAM), which catalyzes glucosinolate formation, strongly resembles another enzyme with a completely different function: The enzyme IPMS (isopropylmalate synthase) is involved in the synthesis of the amino acid leucine. However, the scientists found two major structural differences between IPMS and MAM: the last 120 amino acids are absent in MAM, and in the active site of the enzyme, where the substrates react, two amino acids had been exchanged.
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Origin: /Bund/UBA/UFORDAT
Tags: Gen ? Aminosäure ? Thiocyanat ? Pflanzengenetik ? Cyanobakterien ? Ökologie ? Enzym ? Futtermittel ? Katalyse ? Pflanzenart ? Struktur-Wirkung-Beziehung ? Proteinbiosynthese ? Biosynthese ? Chemikalien ? Evolution ? Protein ? Studie ? Wirkstoff ? Arabidopsis ? Glucosinolate ? Isopropyl-Malat-Synthase ? Methylthioalkylmalat-Synthase ? Pflanzenphysiologie ? Senfölglucoside ? Sequenzierung ?
Region: Mühlhausen/Thüringen
Bounding boxes: 10.453° .. 10.453° x 51.2217° .. 51.2217°
License: cc-by-nc-nd/4.0
Language: Englisch/English
Time ranges: 2011-01-01 - 2011-03-17
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