1
|
Huang Z, Zou J, Guo M, Zhang G, Gao J, Zhao H, Yan F, Niu Y, Wang GL. An aerotaxis receptor influences invasion of Agrobacterium tumefaciens into its host. PeerJ 2024; 12:e16898. [PMID: 38332807 PMCID: PMC10851874 DOI: 10.7717/peerj.16898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Accepted: 01/16/2024] [Indexed: 02/10/2024] Open
Abstract
Agrobacterium tumefaciens is a soil-borne pathogenic bacterium that causes crown gall disease in many plants. Chemotaxis offers A. tumefaciens the ability to find its host and establish infection. Being an aerobic bacterium, A. tumefaciens possesses one chemotaxis system with multiple potential chemoreceptors. Chemoreceptors play an important role in perceiving and responding to environmental signals. However, the studies of chemoreceptors in A. tumefaciens remain relatively restricted. Here, we characterized a cytoplasmic chemoreceptor of A. tumefaciens C58 that contains an N-terminal globin domain. The chemoreceptor was designated as Atu1027. The deletion of Atu1027 not only eliminated the aerotactic response of A. tumefaciens to atmospheric air but also resulted in a weakened chemotactic response to multiple carbon sources. Subsequent site-directed mutagenesis and phenotypic analysis showed that the conserved residue His100 in Atu1027 is essential for the globin domain's function in both chemotaxis and aerotaxis. Furthermore, deleting Atu1027 impaired the biofilm formation and pathogenicity of A. tumefaciens. Collectively, our findings demonstrated that Atu1027 functions as an aerotaxis receptor that affects agrobacterial chemotaxis and the invasion of A. tumefaciens into its host.
Collapse
Affiliation(s)
- Zhiwei Huang
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Junnan Zou
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Minliang Guo
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou City, Jiangsu Province, China
| | - Guoliang Zhang
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Jun Gao
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Hongliang Zhao
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Feiyu Yan
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Yuan Niu
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| | - Guang-Long Wang
- Jiangsu Provincial Agricultural Green and Low Carbon Production Technology Engineering Research Center, School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai’an, Jiangsu Province, China
| |
Collapse
|
2
|
Jiao H, Xu W, Hu Y, Tian R, Wang Z. Citric Acid in Rice Root Exudates Enhanced the Colonization and Plant Growth-Promoting Ability of Bacillus altitudinis LZP02. Microbiol Spectr 2022; 10:e0100222. [PMID: 36264248 PMCID: PMC9769925 DOI: 10.1128/spectrum.01002-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 09/24/2022] [Indexed: 01/05/2023] Open
Abstract
Exploration of the underlying mechanisms of plant-microbe interactions is very important. In the present study, citric acid in the root exudates of rice significantly enhanced the colonization of Bacillus altitudinis LZP02 in the rhizosphere. According to the results of transcriptome and reverse transcription-quantitative PCR or analyses, citric acid increased the expression of several genes involved in bacterial chemotaxis and biofilm formation in B. altitudinis LZP02. In addition, citric acid also increased the expression of several genes associated with S-adenosylmethionine biosynthesis and metabolism. Interestingly, the secretion of citric acid by rice roots could be increased by inoculation with B. altitudinis LZP02. The result indicated that citric acid might be a vital signal in the interaction between rice and B. altitudinis LZP02. Further verification showed that citric acid enhanced the plant growth-promoting ability of B. altitudinis LZP02. IMPORTANCE In a previous study, the mechanism by which citric acid in rice root exudates enhanced the colonization of Bacillus altitudinis LZP02 was discovered. The present study verified that citric acid increased the recruitment and rice growth-promoting ability of B. altitudinis LZP02. These findings serve as an interesting case for explaining the underlying mechanisms of plant-microbe interactions. Henceforth, citric acid and B. altitudinis LZP02 could be exploited for the development of sustainable agronomy.
Collapse
Affiliation(s)
- Huiwen Jiao
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| | - Weihui Xu
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| | - Yunlong Hu
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| | - Renmao Tian
- Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, Illinois, USA
| | - Zhigang Wang
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| |
Collapse
|
3
|
Wang H, Zhang M, Xu Y, Zong R, Xu N, Guo M. Agrobacterium fabrum atu0526-Encoding Protein Is the Only Chemoreceptor That Regulates Chemoattraction toward the Broad Antibacterial Agent Formic Acid. BIOLOGY 2021; 10:biology10121345. [PMID: 34943260 PMCID: PMC8698456 DOI: 10.3390/biology10121345] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/11/2021] [Accepted: 12/13/2021] [Indexed: 12/25/2022]
Abstract
Soil-born plant pathogens, especially Agrobacterium, generally navigate their way to hosts through recognition of the root exudates by chemoreceptors. However, there is still a lack of appropriate identification of chemoreceptors and their ligands in Agrobacterium. Here, Atu0526, a sCache-type chemoreceptor from Agrobacterium fabrum C58, was confirmed as the receptor of a broad antibacterial agent, formic acid. The binding of formic acid to Atu0526 was screened using a thermo shift assay and verified using isothermal titration calorimetry. Inconsistent with the previously reported antimicrobial properties, formic acid was confirmed to be a chemoattractant to A. fabrum and could promote its growth. The chemotaxis of A. fabrum C58 toward formic acid was completely lost with the knock-out of atu0526, and regained with the complementation of the gene, indicating that Atu0526 is the only chemoreceptor for formic acid in A. fabrum C58. The affinity of formic acid to Atu0526LBD significantly increased after the arginine at position 115 was replaced by alanine. However, in vivo experiments showed that the R115A mutation fully abolished the chemotaxis of A. fabrum toward formic acid. Molecular docking based on a predicted 3D structure of Atu0526 suggested that the arginine may provide "an anchorage" for formic acid to pull the minor loop, thereby forming a conformational change that generates the ligand-binding signal. Collectively, our findings will promote an understanding of sCache-type chemoreceptors and their signal transduction mechanism.
Collapse
|
4
|
Li Q, Guo A, Ma Y, Liu L, Liu W, Zhong Y, Zhang Y. Gene Analysis of Listeria monocytogenes Suspended Aggregates Induced by Ralstonia insidiosa Cell-Free Supernatants under Nutrient-Poor Environments. Microorganisms 2021; 9:2591. [PMID: 34946191 PMCID: PMC8704912 DOI: 10.3390/microorganisms9122591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 01/08/2023] Open
Abstract
Listeria monocytogenes is a zoonotic food-borne pathogen. The production of food-borne pathogenic bacteria aggregates is considered to be a way to improve their resistance and persistence in the food chain. Ralstonia insidiosa has been shown to induce L. monocytogenes to form suspended aggregates, but induction mechanisms remain unclear. In the study, the effect of R. insidiosa cell-free supernatants cultured in 10% TSB medium (10% RIS) on the formation of L. monocytogenes suspended aggregates was evaluated. Next, the Illumina RNA sequencing was used to compare the transcriptional profiles of L. monocytogenes in 10% TSB medium with and without 10% RIS to identify differentially expressed genes (DEGs). The result of functional annotation analysis of DEGs indicated that these genes mainly participate in two component system, bacterial chemotaxis and flagellar assembly. Then the reaction network of L. monocytogenes suspended aggregates with the presence of 10% RIS was summarized. The gene-deletion strain of L. monocytogenes was constructed by homologous recombination. The result showed that cheA and cheY are key genes in the formation of suspended aggregates. This research is the preliminary verification of suspended aggregates' RNA sequencing and is helpful to analyze the aggregation mechanisms of food-borne pathogenic bacteria from a new perspective.
Collapse
Affiliation(s)
- Qun Li
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agriculture University, Wuhan 430070, China; (Q.L.); (L.L.); (W.L.); (Y.Z.); (Y.Z.)
| | - Ailing Guo
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agriculture University, Wuhan 430070, China; (Q.L.); (L.L.); (W.L.); (Y.Z.); (Y.Z.)
| | - Yi Ma
- Hubei Provincial Institute for Food Supervision and Test, Wuhan 430070, China
| | - Ling Liu
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agriculture University, Wuhan 430070, China; (Q.L.); (L.L.); (W.L.); (Y.Z.); (Y.Z.)
| | - Wukang Liu
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agriculture University, Wuhan 430070, China; (Q.L.); (L.L.); (W.L.); (Y.Z.); (Y.Z.)
| | - Yuan Zhong
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agriculture University, Wuhan 430070, China; (Q.L.); (L.L.); (W.L.); (Y.Z.); (Y.Z.)
| | - Yawen Zhang
- National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agriculture University, Wuhan 430070, China; (Q.L.); (L.L.); (W.L.); (Y.Z.); (Y.Z.)
| |
Collapse
|