Search results for "STREPTOMYCES COELICOLOR"

From tryptophan metabolism to peptide antibiotic production in Streptomyces coelicolor

2009

The tryptophan is a precursor of the lipopeptide calcium dependent antibiotic (CDA), produced from Streptomyces coelicolor and closely related to important antibiotics such as daptomycin. We have focused our attention on the correlation between CDA production and tryptophan metabolism in order to identify new strategies aimed at increasing the production of peptide antibiotics.

Epigenetic influence on Streptomyces coelicolor morphological and physiological differentiation

2017

DNA methylation is an epigenetic modification regulating many aspects of biological processes; for instance, in bacteria adenine methylation is well known to be associated with DNA repair and coordination of replication, while the role of cytosine methylation has been elucidated only in a few examples. Streptomyces coelicolor is a mycelial soil microorganism, producer of several antibiotics, with a complex life cycle that includes three different cell types: unigenomic spores, a compartmentalized mycelium (MI) and a multinucleated mycelium (MII). The main objective of this study was to investigate the role of DNA cytosine methylation along the morphological and physiological differentiation…

Streptomyces coelicolor secretoma protects astrocytes from oxidative stress

2016

Streptomycetes are gram-positive bacteria that produce about 2/3 of pharmaceutically active secondary metabolites, such as antibiotics, and anti-tumor, immunosuppressive, antifungal and antiparasitic agents. In this study, we investigated the possible effects of Streptomyces coelicolor extracts and putative vesicular fraction on primary cultures of rat astrocytes, in both physiological and stressed conditions, induced by treatment with hydrogen peroxide. Briefly, crude extracts and putative vesicular fractions were prepared from two S.coelicolor strains (M145 wild-type strain and bold F166 strain), and used to treat primary astrocytes, which were then also treated with hydrogen peroxide. Da…

trpX: a small orf involved in S. coelicolor tryptophan metabolism

2013

Streptomyces coelicolor membrane vesicles: many messages to be decoded

2020

The small protein SCO2038 controls Streptomyces coelicolor differentiation by modulating tryptophan biosynthesis

2015

Background In Streptomyces coelicolor amino acid metabolism is an important clue of the morphological and physiological differentiation program and, differently from other bacteria, the expression of amino acid biosynthetic genes is not subjected to endproduct negative regulation. In some amino acid biosynthetic gene clusters, such as tryptophan, histidine and proline, small orfs (about 100-300 nucleotides) were identified. These small orfs, such as sco2038, encode proteins whose cellular role have to be elucidated to highlight possible novel and crucial molecular mechanisms controlling amino acid synthesis and, thus, differentiation program. Objectives The aims of this work are: 1. the und…

The dnaK operon of Streptomyces coelicolor encodes a novel heat-shock protein which binds to the promoter region of the operon

1995

Transcriptional studies have demonstrated that the dnaK gene of Streptomyces coelicolor A3(2) is contained within a 4.3 kb operon. The operon is transcribed from a single (transiently) heat-inducible promoter, dnaKp, that resembles the typical vegetative (sigma 70-recognized) eubacterial consensus promoter sequence. dnaK transcription was found to be heat-inducible at all stages of development in surface-grown cultures. In addition, at the normal growth temperature of 30 degrees C, dnaK transcript levels were shown to vary at different stages of development, being more abundant in young germinating cultures and in mycelium undergoing sporogenesis. The nucleotide sequence of the dnaK operon …

Stategie metaboliche indotte dal triptofano in Streptomyces coelicolor

2013

Synthesis of Optically Active N-(4-Hydroxynon-2-enyl)pyrrolidines: Key Building Blocks in the Total Synthesis of Streptomyces coelicolor Butanolide 5…

2021

AbstractStarting from 5-methylhexanal and (S)-configured N-propargylprolinol ethers, coupling delivered N-(4-hydroxynon-2-ynyl)prolinol derivatives as mixtures of C4 diastereomers. Resolution of the epimers succeeded after introduction of an (R)-mandelic ester derivative and subsequent HPLC separation. Alternatively, suitable oxidation gave the corresponding alkynyl ketone. Midland reagent controlled diastereoselective reduction afforded a defined configured propargyl alcohol with high selectivity. LiAlH4 reduction and Mosher analyses of the allyl alcohols enabled structure elucidation. The suitably protected products are used as key intermediates in enantioselective Streptomyces γ-butyrola…

Tryptophan catabolism via kynurenine production in Streptomyces coelicolor: identification of three genes coding for the enzymes of tryptophan to ant…

2011

Most enzymes involved in tryptophan catabolism via kynurenine formation are highly conserved in Prokaryotes and Eukaryotes. In humans, alterations of this pathway have been related to different pathologies mainly involving the central nervous system. In Bacteria, tryptophan and some of its derivates are important antibiotic precursors. Tryptophan degradation via kynurenine formation involves two different pathways: the eukaryotic kynurenine pathway, also recently found in some bacteria, and the tryptophan-to-anthranilate pathway, which is widespread in microorganisms. The latter produces anthranilate using three enzymes also involved in the kynurenine pathway: tryptophan 2,3-dioxygenase (TD…