Publications by authors named "Nicolai Strizhov"
Article Synopsis
- Pregnenolone and progesterone are crucial steroid hormones in mammals, and new recombinant strains are needed for more efficient microbiological production from sterols.
- A new strain of Mycolicibacterium smegmatis was developed to express steroidogenic enzymes from the bovine adrenal cortex, leading to the production of progesterone and pregnenolone from cholesterol.
- The study demonstrated successful transformation of sterols under optimized conditions, yielding high-purity crystalline pregnenolone, which enhances the potential for efficient hormone production using microbial platforms.
Article Synopsis
- Cytochrome P450scc (CYP11A1) is an enzyme that converts cholesterol into pregnenolone but has low activity with β-sitosterol.
- The study aimed to identify specific amino acid changes in the enzyme that could enhance its ability to convert β-sitosterol.
- Despite modifying the active site through mutations, the results showed that these changes actually decreased enzyme activity, highlighting the crucial roles of specific amino acid residues in the enzyme's function.
Mycobacterium neoaurum strain VKM Ac-1815D produces 4-androstene-3,17-dione as a major compound from phytosterols. Here, we report the complete genome sequence of the strain. The genome consists of a single circular 5,438,190-bp chromosome, with a G+C content of 66.
View Article and Find Full Text PDFDelta-1-pyrroline-5-carboxylate synthetase enzymes, which catalyse the rate-limiting step of proline biosynthesis, are encoded by two closely related P5CS genes in Arabidopsis. Transcription of the P5CS genes is differentially regulated by drought, salinity and abscisic acid, suggesting that these genes play specific roles in the control of proline biosynthesis. Here we describe the genetic characterization of p5cs insertion mutants, which indicates that P5CS1 is required for proline accumulation under osmotic stress.
View Article and Find Full Text PDFThe structural mechanism of the catalytic functioning of shikimate kinase from Mycobacterium tuberculosis was investigated on the basis of a series of high-resolution crystal structures corresponding to individual steps in the enzymatic reaction. The catalytic turnover of shikimate and ATP into the products shikimate-3-phosphate and ADP, followed by release of ADP, was studied in the crystalline environment. Based on a comparison of the structural states before initiation of the reaction and immediately after the catalytic step, we derived a structural model of the transition state that suggests that phosphoryl transfer proceeds with inversion by an in-line associative mechanism.
View Article and Find Full Text PDFThe GABI-Kat population of T-DNA mutagenized Arabidopsis thaliana lines with sequence-characterized insertion sites is used extensively for efficient progress in plant functional genomics. Here we provide details about the establishment of the material, demonstrate the population's functionality and discuss results from quality control studies. T-DNA insertion mutants of the accession Columbia (Col-0) were created by Agrobacterium tumefaciens-mediated transformation.
View Article and Find Full Text PDFA pipeline has been created for the characterization of Arabidopsis thaliana mutants by generating flanking sequence tags (FSTs) and optimized for economic, high-throughput production. The GABI-Kat collection of T-DNA mutagenized A. thaliana plants was used as a source of independent transgenic lines.
View Article and Find Full Text PDFArticle Synopsis
- Arabidopsis plants were genetically modified using double-stranded RNA interference (dsRNAi) to target and silence three callose synthase genes: GSL5, GSL6, and GSL11.
- The study found that wound callose and papillary callose were completely absent in lines with silenced GSL5, indicating its critical role in callose formation, while GSL6 and GSL11 had no such impact.
- Interestingly, while lack of callose in the GSL5 lines slightly increased susceptibility to fungal penetration, it also led to effective growth cessation of some virulent fungi, suggesting a complicated relationship between callose and plant-fungal interactions.
Article Synopsis
- - GABI-Kat SimpleSearch is a database that contains information about T-DNA mutagenized Arabidopsis thaliana lines, specifically focusing on flanking sequence tags (FSTs).
- - The database aligns FSTs with the A. thaliana genome, providing detailed annotations about the insertion sites and the corresponding lines from which these sequences come.
- - A user-friendly web interface allows researchers to perform text-based and sequence-based searches to easily locate T-DNA insertion mutants for their studies.