tryptophan/arabidopsis

Although amino acid auxotrophs are among the most frequently isolated mutations in microorganisms, no mutants that require amino acids have been isolated at the whole plant level. Tryptophan-requiring mutants of the cruciferous plant Arabidopsis thaliana have now been isolated by selecting for

The cruciferous plant Arabidopsis thaliana has two closely related, nonallelic tryptophan synthase beta genes (TSB1 and TSB2), each containing four introns and a chloroplast leader sequence. Both genes are transcribed, although TSB1 produces greater than 90% of tryptophan synthase beta mRNA in leaf

Arabidopsis (Arabidopsis thaliana) penetration (PEN) genes quantitatively contribute to the execution of different forms of plant immunity upon challenge with diverse leaf pathogens. PEN3 encodes a plasma membrane-resident pleiotropic drug resistance-type ATP-binding cassette transporter and is

• A hallmark of the innate immune system of plants is the biosynthesis of low-molecular-weight compounds referred to as secondary metabolites. Tryptophan-derived branch pathways contribute to the capacity for chemical defense against microbes in Arabidopsis thaliana. • Here, we investigated

The first step of tryptophan biosynthesis is catalyzed by anthranilate synthase (AS), which is normally subject to feedback inhibition by tryptophan. Three independent trp5 mutants defective in the Arabidopsis thaliana AS alpha subunit structural gene ASA1 were identified by selection for resistance

A mutant of Arabidopsis thaliana, amt-1, was previously selected for resistance to growth inhibition by the tryptophan analog alpha-methyltryptophan. This mutant had elevated tryptophan levels and exhibited higher anthranilate synthase (AS) activity that showed increased resistance to feedback

Three mutations in the Arabidopsis thaliana gene encoding the alpha subunit of tryptophan synthase were isolated by selection for resistance to 5-methylanthranilate or 5-fluoroindole, toxic analogs of tryptophan pathway intermediates. Plants homozygous for trp3-1 and trp3-2 are light-conditional

Arabidopsis thaliana roots grow in a wavy pattern upon a slanted surface. A novel mutation in the anthranilate synthase alpha 1 (ASA1) gene, named trp5-2wvc1, and mutations in the tryptophan synthase alpha and beta 1 genes (trp3-1 and trp2-1, respectively) confer a compressed root wave phenotype on

BACKGROUND Deoxyuridine triphosphate nucleotidohydrolase (dUTPase) hydrolyzes dUTP to dUMP and pyrophosphate to maintain the cellular thymine-uracil ratio. dUTPase is also a target for cancer chemotherapy. However, the mechanism defining its substrate affinity remains unclear. Sequence comparisons

The expression of the Arabidopsis thaliana PAT1 gene, which encodes the tryptophan biosynthetic enzyme phosphoribosylanthranilate transferase, was investigated using translational fusions of the PAT1 promoter to the GUS reporter gene. Independent stably transformed A. thaliana lines containing a

Tryptophan synthase beta-subunits (TSBs) catalyze the last step in tryptophan biosynthesis, i.e. the condensation of indole and serine yielding tryptophan. In microorganisms two subfamilies of TSBs (here designated as type 1 and type 2) are known, which are only distantly related. Surprisingly, in

Tryptophan is one of the amino acids that cannot be produced in humans and has to be acquired primarily from plants. In Arabidopsis thaliana (Arabidopsis), the tryptophan synthase beta subunit (TSB) genes have been found to catalyze the biosynthesis of tryptophan. Here, we report the isolation and

The cytochrome P450 CYP79B1 from Sinapis alba has been heterologously expressed in Escherichia coli and shown to catalyze the conversion of tryptophan to indole-3-acetaldoxime. Three expression constructs were made, one expressing the native protein and two expressing proteins with different

Plants are suggested to produce their major growth promoting phytohormone, indole-3-acetic acid (IAA), via multiple redundantly operating pathways. Although great effort has been made and plenty of possible routes have been proposed based on experimental evidence, a complete pathway for IAA

Arabidopsis thaliana UV RESISTANCE LOCUS8 (UVR8) has been identified as a photoreceptor for ultraviolet-B (UV-B). Tryptophan (Trp) residues have been shown to play a critical role in the response to UV-B irradiation in UVR8. In this work, we explore the spectroscopic behaviors of Trps in different