Characterization of two trpE genes encoding anthranilate synthase α-subunit in Azospirillum brasilense

Abstract Azospirillum brasilense is a non-photosynthetic member of the family Rhodospirillaceae. Some strains of this bacterium are reported to produce bacterioruberin type of carotenoids, which are generally produced by halophilic or psychrophilic bacteria. Since no other member of Rhodospirillaceae produces bacterioruberin type of carotenoids, we investigated the presence of genes involved in bacterioruberin and spirilloxanthin biosynthetic pathways in A. brasilense Cd. Although genes encoding the spirilloxanthin pathway were absent, homologs of several genes (crtC and crtF) involved in the biosynthesis of bacterioruberins were present in the genome of A. brasilense Cd. However, the homolog of CruF responsible for the final step in bacterioruberin biosynthesis could not be found. We also characterized the carotenoids of A. brasilense Cd using thin-layer chromatography, high-performance liquid chromatography, absorption spectra and high-resolution mass spectrometry (HRMS). Resolution of the methanol extract of carotenoids in ultra-performance liquid chromatography showed nine peaks, out of which six peaks showed absorption spectra characteristic of carotenoids. HRMS of each peak produced 1–14 fragments with different m/z values. Two of these fragments were identified as 19′-hydroxyfucoxanthinol and 8′-apoalloxanthinal, which are the carotenoids found in aquatic microalgae.

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Isolation and Characterization of the Azospirillum brasilense trpE(G) Gene, Encoding Anthranilate Synthase

Current Microbiology ◽

10.1007/s002849900139 ◽

1997 ◽

Vol 34 (1) ◽

pp. 27-32 ◽

Cited By ~ 10

Author(s):

Paul De Troch ◽

Filip Dosselaere ◽

Veerle Keijers ◽

Petra de Wilde ◽

Jos Vanderleyden

Keyword(s):

Azospirillum Brasilense ◽

Anthranilate Synthase ◽

Gene Encoding ◽

Isolation And Characterization

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Isolation and characterization of the genes encoding antimicrobial neutrophil cationic peptides, defensins.

Ensho ◽

10.2492/jsir1981.15.33 ◽

1995 ◽

Vol 15 (1) ◽

pp. 33-41

Author(s):

Isao Nagaoka ◽

Noriko Ishihara ◽

Akimasa Someya ◽

Kazuhisa Iwabuchi ◽

Shin Yomogida ◽

...

Keyword(s):

Cationic Peptides ◽

Isolation And Characterization ◽

Genes Encoding

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Protein complex formation in methionine chain-elongation and leucine biosynthesis

Scientific Reports ◽

10.1038/s41598-021-82790-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Li-Qun Chen ◽

Shweta Chhajed ◽

Tong Zhang ◽

Joseph M. Collins ◽

Qiuying Pang ◽

...

Keyword(s):

Protein Complexes ◽

Complete Characterization ◽

Bimolecular Fluorescence Complementation ◽

Chain Elongation ◽

Substrate Channeling ◽

Leucine Biosynthesis ◽

Protein Complex Formation ◽

Genes Encoding ◽

Isopropylmalate Dehydrogenase

AbstractDuring the past two decades, glucosinolate (GLS) metabolic pathways have been under extensive studies because of the importance of the specialized metabolites in plant defense against herbivores and pathogens. The studies have led to a nearly complete characterization of biosynthetic genes in the reference plant Arabidopsis thaliana. Before methionine incorporation into the core structure of aliphatic GLS, it undergoes chain-elongation through an iterative three-step process recruited from leucine biosynthesis. Although enzymes catalyzing each step of the reaction have been characterized, the regulatory mode is largely unknown. In this study, using three independent approaches, yeast two-hybrid (Y2H), coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC), we uncovered the presence of protein complexes consisting of isopropylmalate isomerase (IPMI) and isopropylmalate dehydrogenase (IPMDH). In addition, simultaneous decreases in both IPMI and IPMDH activities in a leuc:ipmdh1 double mutants resulted in aggregated changes of GLS profiles compared to either leuc or ipmdh1 single mutants. Although the biological importance of the formation of IPMI and IPMDH protein complexes has not been documented in any organisms, these complexes may represent a new regulatory mechanism of substrate channeling in GLS and/or leucine biosynthesis. Since genes encoding the two enzymes are widely distributed in eukaryotic and prokaryotic genomes, such complexes may have universal significance in the regulation of leucine biosynthesis.

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Molecular characterization of clinical carbapenem-resistant Enterobacterales from Qatar

European Journal of Clinical Microbiology & Infectious Diseases ◽

10.1007/s10096-021-04185-7 ◽

2021 ◽

Author(s):

Fatma Ben Abid ◽

Clement K. M. Tsui ◽

Yohei Doi ◽

Anand Deshmukh ◽

Christi L. McElheny ◽

...

Keyword(s):

Common Species ◽

Clinical Samples ◽

Whole Genome ◽

E Coli ◽

Carbapenem Resistant ◽

Genes Encoding ◽

Encoding Genes ◽

Sequence Types ◽

Common Sequence

AbstractOne hundred forty-nine carbapenem-resistant Enterobacterales from clinical samples obtained between April 2014 and November 2017 were subjected to whole genome sequencing and multi-locus sequence typing. Klebsiella pneumoniae (81, 54.4%) and Escherichia coli (38, 25.5%) were the most common species. Genes encoding metallo-β-lactamases were detected in 68 (45.8%) isolates, and OXA-48-like enzymes in 60 (40.3%). blaNDM-1 (45; 30.2%) and blaOXA-48 (29; 19.5%) were the most frequent. KPC-encoding genes were identified in 5 (3.6%) isolates. Most common sequence types were E. coli ST410 (8; 21.1%) and ST38 (7; 18.4%), and K. pneumoniae ST147 (13; 16%) and ST231 (7; 8.6%).

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Expression and function of the cdgD gene, encoding a CHASE–PAS-DGC-EAL domain protein, in Azospirillum brasilense

Scientific Reports ◽

10.1038/s41598-020-80125-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

José Francisco Cruz-Pérez ◽

Roxana Lara-Oueilhe ◽

Cynthia Marcos-Jiménez ◽

Ricardo Cuatlayotl-Olarte ◽

María Luisa Xiqui-Vázquez ◽

...

Keyword(s):

Azospirillum Brasilense ◽

Type Strain ◽

Wild Type Strain ◽

Soil Conditions ◽

Wild Type ◽

Gene Encoding ◽

Wheat Roots ◽

Genes Encoding ◽

In The Wild ◽

Plant Growth Promoting

AbstractThe plant growth-promoting bacterium Azospirillum brasilense contains several genes encoding proteins involved in the biosynthesis and degradation of the second messenger cyclic-di-GMP, which may control key bacterial functions, such as biofilm formation and motility. Here, we analysed the function and expression of the cdgD gene, encoding a multidomain protein that includes GGDEF-EAL domains and CHASE and PAS domains. An insertional cdgD gene mutant was constructed, and analysis of biofilm and extracellular polymeric substance production, as well as the motility phenotype indicated that cdgD encoded a functional diguanylate protein. These results were correlated with a reduced overall cellular concentration of cyclic-di-GMP in the mutant over 48 h compared with that observed in the wild-type strain, which was recovered in the complemented strain. In addition, cdgD gene expression was measured in cells growing under planktonic or biofilm conditions, and differential expression was observed when KNO3 or NH4Cl was added to the minimal medium as a nitrogen source. The transcriptional fusion of the cdgD promoter with the gene encoding the autofluorescent mCherry protein indicated that the cdgD gene was expressed both under abiotic conditions and in association with wheat roots. Reduced colonization of wheat roots was observed for the mutant compared with the wild-type strain grown in the same soil conditions. The Azospirillum-plant association begins with the motility of the bacterium towards the plant rhizosphere followed by the adsorption and adherence of these bacteria to plant roots. Therefore, it is important to study the genes that contribute to this initial interaction of the bacterium with its host plant.

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