Transcriptional analysis and functional characterization of XCC1294 gene encoding a GGDEF domain protein in Xanthomonas campestris pv. campestris

RpfG is a member of a class of wide spread bacterial two-component regulators with an HD-GYP cyclic di-GMP phosphodiesterase domain. In the plant pathogen Xanthomonas campestris pv. campestris (Xcc), RpfG together with the sensor kinase RpfC regulates the synthesis of a range of virulence factors as a response to the cell-cell Diffusible Signaling Factor (DSF). RpfG regulates many different virulence factors by divergent pathways. Physical interaction of RpfG with two diguanylate cyclase (GGDEF) domain proteins controls motility. This is a dynamic interaction that depends upon DSF signaling and involves the conserved GYP motif in the HD-GYP domain. Here we use synthetic peptide overlay technology and yeast two-hybrid analysis in conjunction with alanine substitution mutagenesis to define a motif within the GGDEF domain proteins required for interaction. We show that regulation of motility by the GGDEF domain proteins depends upon this motif. Furthermore, we show by Y2H that both GGDEF domain proteins bind a specific PilZ domain adaptor protein, and this interacts with the pilus motor proteins PilU and PiIT. The results support a model in which DSF signaling influences motility through the interaction of proteins that affect pilus action. The motif required for HD-GYP domain interaction is conserved in a number of GGDEF domain proteins, suggesting that regulation via interdomain interactions may be of broad relevance.

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Characterization of Xanthomonas campestris pv. campestris in Algeria

Phytopathologia Mediterranea ◽

10.36253/phyto-11726 ◽

2021 ◽

Vol 60 (1) ◽

pp. 51-62

Author(s):

Samia LAALA ◽

Sophie CESBRON ◽

Mohamed KERKOUD ◽

Franco VALENTINI ◽

Zouaoui BOUZNAD ◽

...

Keyword(s):

Xanthomonas Campestris ◽

Housekeeping Genes ◽

First Record ◽

Black Rot ◽

Physiological And Biochemical Characteristics ◽

Main Production ◽

Production Areas ◽

Cruciferous Plants ◽

Xanthomonas Campestris Pv Campestris

Xanthomonas campestris pv. campestris (Xcc) causes the black rot of cruciferous plants. This seed-borne bacterium is considered as the most destructive disease to cruciferous crops. Although sources of contamination are various, seeds are the main source of transmission. Typical symptoms of black rot were first observed in 2011 on cabbage and cauliflower fields in the main production areas of Algeria. Leaf samples displaying typical symptoms were collected during 2011 to 2014, and 170 strains were isolated from 45 commercial fields. Xcc isolates were very homogeneous in morphological, physiological and biochemical characteristics similar to reference strains, and gave positive pathogenicity and molecular test results (multiplex PCR with specific primers). This is the first record of Xcc in Algeria. Genetic diversity within the isolates was assessed in comparison with strains isolated elsewhere. A multilocus sequence analysis based on two housekeeping genes (gyrB and rpoD) was carried out on 77 strains representative isolates. The isolates grouped into 20 haplotypes defined with 68 polymorphic sites. The phylogenetic tree obtained showed that Xcc is in two groups, and all Algerian strains clustered in group 1 in three subgroups. No relationships were detected between haplotypes and the origins of the seed lots, the varieties of host cabbage, the years of isolation and agroclimatic regions.

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Cloning and functional characterization of the gene encoding the transcription factor Acel in the basidiomycete Phanerochaete chrysosporium

Biological Research ◽

10.4067/s0716-97602006000500007 ◽

2006 ◽

Vol 39 (4) ◽

Cited By ~ 6

Author(s):

RUBÉN POLANCO ◽

PAULO CANESSA ◽

ALEXIS RIVAS ◽

LUIS F LARRONDO ◽

SERGIO LOBOS ◽

...

Keyword(s):

Transcription Factor ◽

Phanerochaete Chrysosporium ◽

Functional Characterization ◽

Gene Encoding

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Functional characterization of the Haemophilus influenzae 4.5S RNA

Canadian Journal of Microbiology ◽

10.1139/w97-124 ◽

1998 ◽

Vol 44 (1) ◽

pp. 91-94

Author(s):

G Scott Jenkins ◽

Mark S Chandler ◽

Pamela S Fink

Keyword(s):

Haemophilus Influenzae ◽

Functional Characterization ◽

Coli Strain ◽

Northern Analysis ◽

Gene Encoding ◽

E Coli ◽

Functional Homolog ◽

Polymerase Chain ◽

4.5S Rna

The putative 4.5S RNA of Haemophilus influenzae was identified in the genome by computer analysis, amplified by the polymerase chain reaction, and cloned. We have determined that this putative 4.5S RNA will complement an Escherichia coli strain conditionally defective in 4.5S RNA production. The predicted secondary structures of the molecules were quite similar, but Northern analysis showed that the H. influenzae RNA was slightly larger than the E. coli RNA. The H. influenzae gene encoding this RNA is the functional homolog of the ffs gene in E. coli. Key words: ffs gene, complementation studies, small RNA, prokaryotic genetics.

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