Search results for "gene cluster"
showing 10 items of 78 documents
Out of the Abyss: Genome and Metagenome Mining Reveals Unexpected Environmental Distribution of Abyssomicins.
2020
AbstractNatural products have traditionally been discovered through the screening of culturable microbial isolates from all sort of environments. The sequencing revolution allowed the identification of dozens of biosynthetic gene clusters (BGCs) within single bacterial genomes, either from cultured or uncultured strains. However, we are still far from fully exploiting the microbial reservoir, as most of the species are non-model organisms with complex regulatory systems and yet recalcitrant to be engineered. Today, genomic and metagenomic data produced by laboratories worldwide covering the most different natural and artificial environments on Earth, are an invaluable source of raw informat…
Selection on Coding Regions Determined Hox7 Genes Evolution
2003
The important role of Hox genes in determining the regionalization of the body plan of the vertebrates makes them invaluable candidates for evolutionary analyses regarding functional and morphological innovation. Gene duplication and gene loss led to a variable number of Hox genes in different vertebrate lineages. The evolutionary forces determining the conservation or loss of Hox genes are poorly understood. In this study, we show that variable selective pressures acted on Hox7 genes in different evolutionary lineages, with episodes of positive selection occurring after gene duplications. Tests for functional divergence in paralogs detected significant differentiation in a region known to …
Sequence features and evolutionary mechanisms in the chicken avidin gene family
2001
The chicken avidin gene family comprises the avidin gene (avd) and several homologous avidin-related genes (avrs). The sequences of the avr genes are nearly identical to each other but exhibit nonrandomly distributed, frequently nonsynonymous nucleotide substitutions compared to avd. In this study, we determined the genetic distances and the phylogeny of the avd and avr genes and found differences between different exons and introns. Our results suggest the involvement of biased gene conversion in the evolution of the genes. Furthermore, one of the genes was identified as a putative fusion gene. The occurrence of both gene conversion and recombination supports the models suggesting a common…
Expression of the succinate dehydrogenase genes (sdhCAB) from the facultatively anaerobic paenibacillus macerans during aerobic growth
1998
Paenibacillus (formerly Bacillus) macerans is capable of succinate oxidation under oxic conditions and fumarate reduction under anoxic conditions. The reactions are catalyzed by different enzymes, succinate dehydrogenase (Sdh) and fumarate reductase (Frd). The genes encoding Sdh (sdhCAB) were analyzed. The gene products of sdhA and sdhB were similar to the subunits of known Sdh and Frd enzymes. The hydrophobic subunit SdhC showed close sequence similarity to the class of Sdh/Frd enzymes containing diheme cytochrome b. From the sdhCAB gene cluster two transcripts were produced, one comprising sdhCAB, the other sdhAB. The transcripts were found only during aerobic growth, and the amount was d…
Genome-wide significant association between alcohol dependence and a variant in the ADH gene cluster
2011
Alcohol dependence (AD) is an important contributory factor to the global burden of disease. The etiology of AD involves both environmental and genetic factors, and the disorder has a heritability of around 50%. The aim of the present study was to identify susceptibility genes for AD by performing a genome-wide association study (GWAS). The sample comprised 1333 male in-patients with severe AD according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, and 2168 controls. These included 487 patients and 1358 controls from a previous GWAS study by our group. All individuals were of German descent. Single-marker tests and a polygenic score-based analysis to assess the …
Potent Inhibitor of Human Trypsins from the Aeruginosin Family of Natural Products
2021
Funding Information: We would like to thank A. Löfhjelm and L. Saari for excellent technical assistance. This work was supported by a Sigrid Jusélius Foundation grant to H.K. and the Academy of Finland funding (321809) to T.S. We would also like to thank the Erkko Foundation and Nordforsk Nordic center of Excellency NordAqua (project number #82845) and University of Helsinki’s Doctoral Programme in Microbiology and Biotechnology funding to M.N.A. D.O.A. was supported by a postdoctoral research fellowship from the São Paulo Research Foundation (FAPESP #2018/01563-2). We thank Biocenter Kuopio for the use of their facilities for molecular modeling and MD simulations. We thank the DNA Sequenci…
Genetic characterization of the Mascaruna goat, a Sicilian autochthonous population, using molecular markers
2013
The aim of this work was to characterize a Sicilian autochthonous goat population using microsatellite markers and genetic polymorphisms at the casein genes. In order to investigate the genetic structure of the Mascaruna goat, a total of 60 (20 Girgentana, 20 mixed populations, and 20 Mascaruna) individuals were analyzed, using a panel of 18 microsatellite markers. Moreover, the Mascaruna goats were genotyped at casein loci using several molecular techniques. Based on the genetic structure at casein genes, the Mascaruna goat was similar to most goat breeds from the Mediterranean area, which are characterized by the predominance of strong alleles. The low value of genetic differentiation amo…
BIOSYNTHESIS OF HEROCYCLES. FROM ISOLATION TO GENE CLUSTER
2015
This book describes biosynthetic methods to synthesize heterocyclic compounds, offering a guide for the development of new drugs based on natural products. The authors explain the role of natural products in chemistry and their formation along with important analytical methods and techniques for working with heterocycles. • Covers methods and techniques: isotopic labelling, enzymes and mutants, and pathway identification • Provides a thorough resource of information specifically on heterocyclic natural products and their practical biosynthetic relevance • Explains the role of natural products in chemistry and their formation • Discusses gene cluster identification and the use of biogenetic …
F17-like fimbriae from an invasive Escherichia coli strain producing cytotoxic necrotizing factor type 2 toxin
1994
The F17b fimbriae encoded by the transmissible virulence plasmid Vir, also coding for cytotoxic necrotizing factor type 2, were characterized. A 5.7-kb region of Vir mediates in vitro N-acetylglucosamine-sensitive adhesion to calf intestinal villi. Sequence analysis revealed that this region codes for a structural subunit and an adhesin closely related to the F17-A and F17-G proteins encoded by the F17 fimbrial gene cluster. The F17b-A gene presents an open reading frame of 540 bp encoding a polypeptide of 180 amino acids with a putative signal peptide of 21 residues. The mature protein shows an identity of 74% with the F17-A structural subunit. This 20-kDa protein is recognized by antiseru…
Tryptophan promotes morphological and physiological differentiation in Streptomyces coelicolor.
2015
The molecular mechanisms regulating tryptophan biosynthesis in actinomycetes are poorly understood; similarly, the possible roles of tryptophan in the differentiation program of microorganism life-cycle are still underexplored. To unveil the possible regulatory effect of this amino acid on gene expression, an integrated study based on quantitative teverse transcription-PCR (qRT-PCR) and proteomic approaches was performed on the actinomycete model Streptomyces coelicolor. Comparative analyses on the microorganism growth in a minimal medium with or without tryptophan supplementation showed that biosynthetic trp gene expression in S. coelicolor is not subjected to a negative regulation by the …