LhnR and upstream operon LhnABC in Agrobacterium vitis regulate the induction of tobacco hypersensitive responses, grape necrosis and swarming motility

ABSTRACTA plasmid, pTA163, inEscherichia colicontained an approximately 34-kb gene fragment fromPseudomonas putidaJYR-1 that included the genes responsible for the metabolism oftrans-anethole to protocatechuic acid. Three Tn5-disrupted open reading frame 10 (ORF 10) mutants of plasmid pTA163 lost their abilities to catalyzetrans-anethole. Heterologously expressed ORF 10 (1,047 nucleotides [nt]) under a T7 promoter inE. colicatalyzed oxidative cleavage of a propenyl group oftrans-anethole to an aldehyde group, resulting in the production ofpara-anisaldehyde, and this gene was designatedtao(trans-anetholeoxygenase). The deduced amino acid sequence of TAO had the highest identity (34%) to a hypothetical protein ofAgrobacterium vitisS4 and likely contained a flavin-binding site. Preferred incorporation of an oxygen molecule from water intop-anisaldehyde using18O-labeling experiments indicated stereo preference of TAO for hydrolysis of the epoxide group. Interestingly, unlike the narrow substrate range of isoeugenol monooxygenase fromPseudomonas putidaIE27 andPseudomonas nitroreducensJin1, TAO fromP. putidaJYR-1 catalyzed isoeugenol,O-methyl isoeugenol, and isosafrole, all of which contain the 2-propenyl functional group on the aromatic ring structure. Addition of NAD(P)H to the ultrafiltered cell extracts ofE. coli(pTA163) increased the activity of TAO. Due to the relaxed substrate range of TAO, it may be utilized for the production of various fragrance compounds from plant phenylpropanoids in the future.

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Epr plays a key role in DegU-mediated swarming motility ofBacillus subtilis

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.2009.01596.x ◽

2009 ◽

Vol 295 (2) ◽

pp. 187-194 ◽

Cited By ~ 7

Author(s):

Monica Gupta ◽

Kestur Krishnamurthy Rao

Keyword(s):

Ofbacillus Subtilis ◽

Swarming Motility

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Pseudomonas aeruginosa PAO 1 In Vitro Time–Kill Kinetics Using Single Phages and Phage Formulations—Modulating Death, Adaptation, and Resistance

Antibiotics ◽

10.3390/antibiotics10070877 ◽

2021 ◽

Vol 10 (7) ◽

pp. 877

Author(s):

Ana Mafalda Pinto ◽

Alberta Faustino ◽

Lorenzo M. Pastrana ◽

Manuel Bañobre-López ◽

Sanna Sillankorva

Keyword(s):

Pseudomonas Aeruginosa ◽

Phage Therapy ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Chronic Infections ◽

Swarming Motility ◽

Resistance Development ◽

Healthcare Settings ◽

Time Kill

Pseudomonas aeruginosa is responsible for nosocomial and chronic infections in healthcare settings. The major challenge in treating P. aeruginosa-related diseases is its remarkable capacity for antibiotic resistance development. Bacteriophage (phage) therapy is regarded as a possible alternative that has, for years, attracted attention for fighting multidrug-resistant infections. In this work, we characterized five phages showing different lytic spectrums towards clinical isolates. Two of these phages were isolated from the Russian Microgen Sextaphage formulation and belong to the Phikmvviruses, while three Pbunaviruses were isolated from sewage. Different phage formulations for the treatment of P. aeruginosa PAO1 resulted in diversified time–kill outcomes. The best result was obtained with a formulation with all phages, prompting a lower frequency of resistant variants and considerable alterations in cell motility, resulting in a loss of 73.7% in swimming motility and a 79% change in swarming motility. These alterations diminished the virulence of the phage-resisting phenotypes but promoted their growth since most became insensitive to a single or even all phages. However, not all combinations drove to enhanced cell killings due to the competition and loss of receptors. This study highlights that more caution is needed when developing cocktail formulations to maximize phage therapy efficacy. Selecting phages for formulations should consider the emergence of phage-resistant bacteria and whether the formulations are intended for short-term or extended antibacterial application.

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The Presence and Characterization of a virF Gene on Agrobacterium vitis Ti Plasmids

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1998.11.5.429 ◽

1998 ◽

Vol 11 (5) ◽

pp. 429-433 ◽

Cited By ~ 14

Author(s):

B. Schrammeijer ◽

J. Hemelaar ◽

P. J. J. Hooykaas

Keyword(s):

Amino Acids ◽

Agrobacterium Tumefaciens ◽

Molecular Mass ◽

Promoter Region ◽

Consensus Sequence ◽

Tumor Formation ◽

Nicotiana Glauca ◽

Agrobacterium Vitis ◽

Ti Plasmids

Octopine and nopaline strains of Agrobacterium tumefaciens differ in their ability to induce tumors on Nicotiana glauca. The presence of a virF locus on the octopine Ti plasmid makes N. glauca a host plant for these strains, indicating that the VirF protein is a host-range determinant. Here we show the presence of a virF locus not only on the Agrobacterium vitis octopine/cucumopine plasmids pTiAg57 and pTiTm4, but also on the nopaline Ti plas-mids pTiAT1, pTiAT66a, and pTiAT66b. On the octopine Ti plasmids from A. tumefaciens the virF gene is located between the virE locus and the left border of the T-region. In contrast, the virF gene on Ti plasmids of A. vitis is located at the very left end of the vir-region near the virA locus. The virF gene of pTiAg57 has been sequenced and codes for a protein of 202 amino acids with a molecular mass of 22,280 Da. Comparison showed that the virF gene from A. vitis strain Ag57 is almost identical to that from A. tumefaciens octopine strains. The transcription of the pTiAg57 virF is inducible by the plant phenolic compound acetosyringone through the presence of a vir-box consensus sequence in its promoter region. The VirF protein from pTiAg57 can complement octopine A. tumefaciens strains deleted for virF as shown by tumor formation on N. glauca.

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Inhibition of Swarming motility of Pseudomonas aeruginosa by Methanol extracts of Alpinia officinarum Hance. and Cinnamomum tamala T. Nees and Eberm

Natural Product Research ◽

10.1080/14786419.2017.1340289 ◽

2017 ◽

Vol 32 (11) ◽

pp. 1307-1311 ◽

Cited By ~ 2

Author(s):

Divya Lakshmanan ◽

Jishudas Nanda ◽

K. Jeevaratnam

Keyword(s):

Pseudomonas Aeruginosa ◽

Swarming Motility ◽

Methanol Extracts ◽

Alpinia Officinarum ◽

Cinnamomum Tamala

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Multiple Promoters Contribute to Swarming and the Coordination of Transcription with Flagellar Assembly in Salmonella

Journal of Bacteriology ◽

10.1128/jb.00093-10 ◽

2010 ◽

Vol 192 (18) ◽

pp. 4752-4762 ◽

Cited By ~ 23

Author(s):

Christopher E. Wozniak ◽

Fabienne F. V. Chevance ◽

Kelly T. Hughes

Keyword(s):

Transcriptional Regulation ◽

Stationary Phase ◽

Basal Body ◽

Environmental Conditions ◽

Swarming Motility ◽

Multiple Promoters ◽

Associated Proteins ◽

Flagellar Assembly

ABSTRACT In Salmonella, there are three classes of promoters in the flagellar transcriptional hierarchy. This organization allows genes needed earlier in the construction of flagella to be transcribed before genes needed later. Four operons (fliAZY, flgMN, fliDST, and flgKL) are expressed from both class 2 and class 3 promoters. To investigate the purpose for expressing genes from multiple flagellar promoters, mutants were constructed for each operon that were defective in either class 2 transcription or class 3 transcription. The mutants were checked for defects in swimming through liquids, swarming over surfaces, and transcriptional regulation. The expression of the hook-associated proteins (FlgK, FlgL, and FliD) from class 3 promoters was found to be important for swarming motility. Both flgMN promoters were involved in coordinating class 3 transcription with the stage of assembly of the hook-basal body. Finally, the fliAZY class 3 promoter lowered class 3 transcription in stationary phase. These results indicate that the multiple flagellar promoters respond to specific environmental conditions and help coordinate transcription with flagellar assembly.

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