Differential Protein Expression Analysis of Two Sugarcane Varieties in Response to Diazotrophic Plant Growth-Promoting Endophyte Enterobacter roggenkampii ED5

Abstract

Plant endophytic bacteria have many vital roles in plant growth promotion (PGP), such as nitrogen (N) fixation and resistance to biotic and abiotic stresses. In this study, the seedlings of sugarcane varieties B8 (requires a low concentration of nitrogen for growth) and GT11 (requires a high concentration of nitrogen for growth) were inoculated with endophytic diazotroph Enterobacter roggenkampii ED5, which exhibits multiple PGP traits, isolated from sugarcane roots. The results showed that the inoculation with E. roggenkampii ED5 promoted the growth of plant significantly in both sugarcane varieties. 15N detection at 60 days post-inoculation proved that the inoculation with strain ED5 increased the total nitrogen concentration in the leaf and root than control in both sugarcane varieties, which was higher in B8. Biochemical parameters and phytohormones in leaf were analyzed at 30 and 60 days after the inoculation. The results showed that the inoculation with E. roggenkampii ED5 improved the activities of superoxide dismutase (SOD), catalase (CAT), NADH-glutamate dehydrogenase (NADH-GDH), glutamine synthetase (GS), and endo-β-1,4-glucanase, and the contents of proline and indole acetic acid (IAA) in leaf, and it was generally more significant in B8 than in GT11. Tandem Mass Tags (TMT) labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to perform comparative proteomic analysis in the sugarcane leaves at 30 days after inoculation with strain ED5. A total of 27,508 proteins were detected, and 378 differentially expressed proteins (DEPs) were found in the treated sugarcane variety B8 (BE) as compared to control (BC), of which 244 were upregulated and 134 were downregulated. In contrast, a total of 177 DEPs were identified in the treated sugarcane variety GT11 (GE) as compared to control (GC), of which 103 were upregulated and 74 were downregulated. The DEPs were associated with nitrogen metabolism, photosynthesis, starch, sucrose metabolism, response to oxidative stress, hydrolase activity, oxidative phosphorylation, glutathione metabolism, phenylpropanoid metabolic process, and response to stresses in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. To the best of our knowledge, this is the first proteomic approach to investigate the molecular basis of the interaction between N-fixing endophytic strain E. roggenkampii ED5 and sugarcane.

Complete genome analysis of sugarcane root associated endophytic diazotroph Pseudomonas aeruginosa DJ06 revealing versatile molecular mechanism involved in sugarcane development

“…At the same time, it was found that the activities of oxidative stress enzymes (SOD, POD, and CAT) and the content of oxidative product MDA in sugarcane varieties, GT11 and B8, inoculated with the DJ06 strain was significantly changed as compared with the controls in this study, indicating that the DJ06 strain stimulated the occurrence of physiological responses of sugarcane, and then enhance the ability to adapt to the external environment. The variations in SOD, POD, and MDA activities after inoculation of the DJ06 strain may differ from the genetic variability in the two sugarcane varieties (Guo et al, 2021 ). In addition, this study found that there were mobile genetic elements (MGEs) in the genome of the DJ06 strain, such as the CRISPR system and prophage, which play an important role in PGPB strains for adaptation to the environment, and similar results were also reported in Enterobacter roggenkampii ED5 (Guo et al, 2020 ).…”

“…The coding sequence (CDS), tRNA, and rRNA were predicted by Glimmer 3.02, tRNAscan-SE 2.0, and Barrnap software, respectively. The predicted CDS protein functions were annotated from NR, Swiss prot, Pfam, Gene Ontology (GO), Clusters of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases by using Blast2go 2.0, Diamond 0.8.35, HMMER3.1b2, and other sequence alignment tools (Guo et al, 2021 ).…”

“…IPA-CC33, and Bacillus megaterium IPA-CF6 (Antunes et al, 2019 ). The nitrogen uptake of sugarcane varieties, GT11 and B8, has significantly improved on inoculation of Enterobacter roggenkampii ED5 strain, and physiological enzymatic activities were also considerably changed (Guo et al, 2021 ). Some PGPBs were used for biocontrol due to having an effective inhibitory effect on plant pathogens.…”

Complete Genome Sequence of Enterobacter roggenkampii RX.G5M56, a C1-Metabolizing Strain from a Freshwater Stream in Hong Kong

“…are recognized as human pathogens ( 2 ), E. roggenkampii represents only around 4% of clinical ECC isolates ( 3 – 6 ). Commonly associated with plants ( 7 , 8 ), it has been proposed for crop growth promotion ( 9 ), although its versatile biochemistry includes broad intrinsic antimicrobial resistance ( 10 ) and the ability to hasten the corrosion of steel ( 11 ). As endophytes and in the rhizosphere, isolates of E. roggenkampii may produce indole-3-acetic acid and siderophores, solubilize phosphate, and fix nitrogen ( 7 , 12 ).…”

Molecular mechanism of endophytic bacteria DX120E regulating polyamine metabolism and promoting plant growth in sugarcane

“…The beneficial impacts of the endophytic bacteria on host plants are usually greater than those provided by many rhizosphere bacteria. They can benefit host plants directly by improving plant nutrient uptake ( Guo et al., 2021 ) and modulating growth and stress-related phytohormones ( Nivedita et al., 2020 ; Cipriano et al., 2021 ).…”