The farnesyltransferase α-subunit (FTA) may be involved in the regulation of defence responses against pathogens in plants. In this study, this gene was amplified from Catharanthus roseus (CrFTA gene). The cDNA was found to be 1 403 bp long, and encodes a putative protein of 331 amino acids that contains a conserved PPTA motif. The phylogenetic analysis showed that the sequence of CrFTA is the most similar to that from Coffea canephora. The qRT-PCR assays indicated that CrFTA is expressed in the leaves, stems, and roots. During a Candidatus Liberibacter asiaticus (Ca. L. asiaticus) infection, the CrFTA expression levels significantly increased and reached 18-fold that measured in the control group, after which its expression decreased gradually from 22 days after top-grafting (DAT) to the end of the experiment. Spray application of Manumycin A (ManuA), a specific inhibitor of farnesyltransferase, on the leaves of C. roseus plants caused a significant decrease in the CrFTA expression and a significant increase in the Ca. L. asiaticus positivity percentage after top-grafting with the Ca. L. asiaticus-infected shoots compared with the groups not treated with ManuA. Furthermore, ABA had no significant effect on the relative expression of CrFTA and the number of Ca. L. asiaticus-positive plants. These results suggest that CrFTA most likely plays a role in mediating the tolerance to a Ca. L. asiaticus infection in C. roseus.
Microbiology is in a new age in which sequence databases are primary sources of information about many microbes. However, in-depth analysis of environmental genomes thus retrieved is essential to substantiate the new knowledge.
We report here the metagenome-assembled draft genome of an uncultured filamentous anoxygenic phototroph of the phylum
Roseilinea sp. strain NK_OTU-006,” recovered from hot spring-associated microbial mats. The 3.6-Mb genome is estimated to be 94% complete and comprises 117 contigs encoding 3,203 predicted genes, including a full-length rRNA operon.
Dehalogenimonas etheniformans” strain GP couples growth with the reductive dechlorination of vinyl chloride and several polychlorinated ethenes. The genome sequence comprises a circular 2.07-Mb chromosome with a G+C content of 51.9% and harbors 50 putative reductive dehalogenase genes.
Anaerobic ammonium oxidizing bacteria (anammox bacteria) are contributing significantly to the nitrogen cycle and are successfully used in wastewater treatment. Due to the lack of complete genomes in the databases, little is known about the stability and variability of their genomes and how the genomes evolve in response to changing environments.
Here we report the complete genome of the anammox bacterium “Candidatus Kuenenia stuttgartiensis” strain CSTR1 which was enriched planktonically in a semi-continuous stirred-tank reactor. A comparison of the genome of strain CSTR1 with the genome of “Ca. Kuenenia stuttgartiensis” MBR1 and the draft genome of KUST showed > 99% average nucleotide identity among all. Rearrangements of large genomic regions were observed, most of which were associated with transposase genes. Phylogenetic analysis suggests that strain MBR1 is more distantly related to the other two strains. Proteomic analysis of actively growing cells of strain CSTR1 (growth rate ~ 0.33 d− 1) failed to detect the annotated cytochrome cd1-type nitrite reductase (NirS) although in total 1189 proteins were found in the proteome. Yet, this NirS was expressed when strain CSTR1 was under stress or starvation (growth rate < 0.06 d− 1). We also observed large sequence shifts in the strongly expressed S-layer protein compared to other “Ca. Kuenenia” strains, indicating the formation of hybrids of genes encoding the surface proteins.
“Ca. Kuenenia” strains appear to be relatively stable in their basic physiological traits, but show high variability in overall genome structure and surface proteins.
Chloroflexales bacteria are mostly known as filamentous anoxygenic phototrophs that thrive as members of the microbial communities of hot spring cyanobacterial mats. Recently, we described many new Chloroflexales species from non-thermal environments and showed that mesophilic Chloroflexales are more diverse than previously expected. Most of these species were isolated from aquatic environments of mid-latitudes. Here, we present the comprehensive characterization of a new filamentous multicellular anoxygenic phototrophic Chloroflexales bacterium from an Arctic coastal environment (Kandalaksha Gulf, the White Sea). Phylogenomic analysis and 16S rRNA phylogeny indicated that this bacterium belongs to the Oscillochloridaceae family as a new species. We propose that this species be named ‘Candidatus Oscillochloris kuznetsovii’. The genomes of this species possessed genes encoding sulfide:quinone reductase, the nitrogenase complex and the Calvin cycle, which indicate potential for photoautotrophic metabolism. We observed only mesophilic anaerobic anoxygenic phototrophic growth of this novel bacterium. Electron microphotography showed the presence of chlorosomes, polyhydroxyalkanoate-like granules and polyphosphate-like granules in the cells. High-performance liquid chromatography also revealed the presence of bacteriochlorophylls a, c and d as well as carotenoids. In addition, we found that this bacterium is present in benthic microbial communities of various coastal environments of the Kandalaksha Gulf.
The draft genome sequence of a novel “
Liberibacter” species detected in an unidentified species of
(Rutaceae) collected in Bhutan is reported. The total length is 1,408,989 bp with 1,169 coding sequences in 96 contigs, a GC content of 37.3%, and 76 to 77% average nucleotide identity with several other “
. Liberibacter” species.