Enhancing maize drought and heat tolerance: single vs combined plant growth promoting rhizobacterial inoculation.

Maize ( L.), a key staple crop in Sub-Saharan Africa, is particularly vulnerable to concurrent drought and heat stress, which threatens crop yield and food security. Plant growth-promoting rhizobacteria (PGPR) have shown potential as biofertilizers to enhance plant resilience under such abiotic stresses.

A computational and secretome analysis approach reveals exclusive and shared candidate type six secretion system substrates in Pectobacterium brasiliense 1692.

The type 6 secretion system (T6SS) of Gram-negative bacteria (GNB) has implications for bacterial competition, virulence, and survival. For the broad host range pathogen, Pectobacterium brasiliense 1692, T6SS-mediated competition occurs in a tissue-specific manner. However, no other roles have been investigated.

"Order from disordered": Potential role of intrinsically disordered regions in phytopathogenic oomycete intracellular effector proteins.

There is a continuous arms race between pathogens and their host plants. However, successful pathogens, such as phytopathogenic oomycetes, secrete effector proteins to manipulate host defense responses for disease development. Structural analyses of these effector proteins reveal the existence of regions that fail to fold into three-dimensional structures, intrinsically disordered regions (IDRs).

In silico secretome analyses of the polyphagous root-knot nematode Meloidogyne javanica: a resource for studying M. javanica secreted proteins.

Background: Plant-parasitic nematodes (PPNs) that cause most damage include root-knot nematodes (RKNs) which are a major impediment to crop production. Root-knot nematodes, like other parasites, secrete proteins which are required for parasite proliferation and survival within the host during the infection process.

Results: Here, we used various computational tools to predict and identify classically and non-classically secreted proteins encoded in the Meloidogyne javanica genome.

Bacterial secretion system functions: evidence of interactions and downstream implications.

Unprecedented insights into the biology and functions of bacteria have been and continue to be gained through studying bacterial secretion systems in isolation. This method, however, results in our understanding of the systems being primarily based on the idea that they operate independently, ignoring the subtleties of downstream interconnections. Gram-negative bacteria are naturally able to adapt to and navigate their frequently varied and dynamic surroundings, mostly because of the covert connections between secretion systems.

Rhizosphere bacterial interactions and impact on plant health.

The rhizosphere is a chemically complex environment that harbors a strikingly diverse microbial community. The past few decades have seen a rapid growth in the body of literature on plant-microbe-microbe interactions and plant health. Thus, the aim of this paper is to review current knowledge on plant-microbe-microbe (specifically bacteria) interactions in the rhizosphere and how these influence rhizosphere microbiomes and impact plant health.

Short Linear Motifs (SLiMs) in "Core" RxLR Effectors of var. : a Case of PpRxLR1 Effector.

Oomycetes of the genus encompass several of the most successful plant pathogens described to date. The success of infection by species is attributed to the pathogens' ability to secrete effector proteins that alter the host's physiological processes. Structural analyses of effector proteins mainly from bacterial and viral pathogens have revealed the presence of intrinsically disordered regions that host short linear motifs (SLiMs).

Draft Genome Sequences of Three Identified Rhizobacteria Associated with Maize Rhizosphere.

In this study, we sequenced the entire genomes of three identified rhizobacterial strains associated with maize plantation. Genome annotation of the sequenced data revealed several putative growth-promoting proteins associated with the production of indoleacetic acids and siderophore, the assimilation of nitrogen, and phosphorus solubilization.

Isolation and Characterization of Outer Membrane Vesicles of 1692.

(Pbr) 1692 is an aggressive phytopathogen affecting a broad host range of crops and ornamental plants, including potatoes. Previous research on animal pathogens, and a few plant pathogens, revealed that Outer Membrane Vesicles (OMVs) are part of Gram-negative bacteria's (GNB) adaptive toolkit. For this reason, OMV production and subsequent release from bacteria is a conserved process.

"Core" RxLR effectors in phytopathogenic oomycetes: A promising way to breeding for durable resistance in plants?

Phytopathogenic oomycetes are known to successfully infect their hosts due to their ability to secrete effector proteins. Of interest to many researchers are effectors with the N-terminal RxLR motif (Arginine-any amino acid-Leucine-Arginine). Owing to advances in genome sequencing, we can now comprehend the high level of diversity among oomycete effectors, and similarly, their conservation within and among species referred to here as "ore" xLR ffectors (CREs).

Chemotactic Responses and the Role of Methyl-Accepting Chemotactic Proteins in Ecological Fitness.

To adapt to changing environmental niches, bacteria require taxis, a movement toward or away from a stimulus (ligand). Chemotaxis has been studied in some members of the Soft Rot Pectobacteriaceae (SRP), particularly members of the genus . On the contrary, there are fewer studies on this topic for the other genus in the SRP group, namely .

Novel Two-Component System-Like Elements Reveal Functional Domains Associated with Restriction-Modification Systems and paraMORC ATPases in Bacteria.

Two-component systems (TCS) are important types of machinery allowing for efficient signal recognition and transmission in bacterial cells. The majority of TCSs utilized by bacteria is composed of a sensor histidine kinase (HK) and a cognate response regulator (RR). In the present study, we report two newly predicted protein domains-both to be included in the next release of the Pfam database: Response_reg_2 (PF19192) and HEF_HK (PF19191)-in bacteria which exhibit high structural similarity, respectively, with typical domains of RRs and HKs.

Transcriptome Profiling of Potato ( L.) Responses to Root-Knot Nematode () Infestation during A Compatible Interaction.

Root-knot nematode (RKN) presents a great challenge to Solanaceae crops, including potato. In this study, we investigated transcriptional responses of potato roots during a compatible interaction with . In this respect, differential gene expression of cultivar (cv.

Organize, Don't Agonize: Strategic Success of Species.

Plants are constantly challenged by various environmental stressors ranging from abiotic-sunlight, elevated temperatures, drought, and nutrient deficits, to biotic factors-microbial pathogens and insect pests. These not only affect the quality of harvest but also the yield, leading to substantial annual crop losses, worldwide. Although plants have a multi-layered immune system, phytopathogens such as species of the oomycete genus , can employ elaborate mechanisms to breach this defense.

Horizontally Acquired Quorum-Sensing Regulators Recruited by the PhoP Regulatory Network Expand the Host Adaptation Repertoire in the Phytopathogen .

In this study, we examine the impact of transcriptional network rearrangements driven by horizontal gene acquisition in PhoP and SlyA regulons using as a case study a phytopathosystem comprised of potato tubers and the soft-rot pathogen 1692 (Pb1692). Genome simulations and statistical analyses uncovered the tendency of PhoP and SlyA networks to mobilize lineage-specific traits predicted as horizontal gene transfer at late infection, highlighting the prominence of regulatory network rearrangements in this stage of infection. The evidence further supports the circumscription of two horizontally acquired quorum-sensing regulators ( and ) by the PhoP network.

The Impact of Type VI Secretion System, Bacteriocins and Antibiotics on Bacterial Competition of subsp. and the Regulation of Carbapenem Biosynthesis by Iron and the Ferric-Uptake Regulator.

Unlabelled: The complexity of plant microbial communities provides a rich model for investigating biochemical and regulatory strategies involved in interbacterial competition. Within these niches, the soft rot (SRE) represents an emerging group of plant-pathogens causing soft rot/blackleg diseases resulting in economic losses worldwide in a variety of crops. A preliminary screening using next-generation sequencing of 16S rRNA comparatively analyzing healthy and diseased potato tubers, identified several taxa from to as potential potato endophytes/plant pathogens.

Functional Characterization of a Global Virulence Regulator Hfq and Identification of Hfq-Dependent sRNAs in the Plant Pathogen .

To successfully infect plant hosts, the collective regulation of virulence factors in a bacterial pathogen is crucial. Hfq is an RNA chaperone protein that facilitates the small RNA (sRNA) regulation of global gene expression at the post-transcriptional level. In this study, the functional role of Hfq in a broad host range phytopathogen was determined.

Transcriptome and Comparative Genomics Analyses Reveal New Functional Insights on Key Determinants of Pathogenesis and Interbacterial Competition in and spp.

Soft-rot (SRE), typified by and genera, are phytopathogenic bacteria inflicting soft-rot disease in crops worldwide. By combining genomic information from 100 SRE with whole-transcriptome data sets, we identified novel genomic and transcriptional associations among key pathogenicity themes in this group. Comparative genomics revealed solid linkage between the type I secretion system (T1SS) and the carotovoricin bacteriophage (Ctv) conserved in 96.

Transcriptome Profiling Reveals the EanI/R Quorum Sensing Regulon in Pantoea Ananatis LMG 2665.

LMG 2665 synthesizes and utilizes acyl homoserine lactones (AHLs) for signalling. The complete set of genes regulated by the EanI/R quorum sensing (QS) system in this strain is still not fully known. In this study, RNA-sequencing (RNA-seq) was used to identify the EanI/R regulon in LMG 2665.

Influence of the ferric uptake regulator (Fur) protein on pathogenicity in Pectobacterium carotovorum subsp. brasiliense.

Iron is an important nutrient for the survival and growth of many organisms. In order to survive, iron uptake from the environment must be strictly regulated and maintained to avoid iron toxicity. The ferric uptake regulator protein (Fur) regulates genes involved in iron homeostasis in many bacteria, including phytopathogens.

Evidence for salicylic acid signalling and histological changes in the defence response of Eucalyptus grandis to Chrysoporthe austroafricana.

Eucalyptus species are cultivated for forestry and are of economic importance. The fungal stem canker pathogen Chrysoporthe austroafricana causes disease of varying severity on E. grandis.

Global Gene Expression Analysis of Cross-Protected Phenotype of Pectobacterium atrosepticum.

The ability to adapt to adverse conditions permits many bacterial species to be virtually ubiquitous and survive in a variety of ecological niches. This ability is of particular importance for many plant pathogenic bacteria that should be able to exist, except for their host plants, in different environments e.g.

RNA-seq Profiling Reveals Defense Responses in a Tolerant Potato Cultivar to Stem Infection by ssp. .

subsp. is a member of the soft rot Enterobacteriaceae (SRE) family that causes tuber soft rot and blackleg diseases of stems in potato plants. Currently, there are no effective chemical strategies for the control of members of the SRE.

Localization and Transcriptional Responses of in Identify Putative Pathogenicity Factors.

is a fungal pathogen that causes the development of stem cankers on susceptible trees. Clones of that are partially resistant and highly susceptible have been identified based on the extent of lesion formation on the stem upon inoculation with These interactions have been used as a model pathosystem to enhance our understanding of interactions between pathogenic fungi and woody hosts, which may be different to herbaceous hosts. In previous research, transcriptomics of host responses in these two clones to suggested roles for salicylic acid and gibberellic acid phytohormone signaling in defense.