1
|
Arana N, Perez Mora B, Permingeat V, Giordano R, Calderone M, Tuttobene M, Klinke S, Rinaldi J, Müller G, Mussi MA. Light regulation in critical human pathogens of clinical relevance such as Acinetobacter baumannii, Staphylococcus aureus and Pseudomonas aeruginosa. Photochem Photobiol Sci 2023; 22:2019-2036. [PMID: 37269546 DOI: 10.1007/s43630-023-00437-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/08/2023] [Indexed: 06/05/2023]
Abstract
It is now clearly recognized that light modulates the physiology of many bacterial chemotrophs, either directly or indirectly. An interesting case are bacterial pathogens of clinical relevance. This work summarizes, discusses, and provides novel complementary information to what is currently known about light sensing and responses in critical human pathogens such as Acinetobacter baumannii, Pseudomonas aeruginosa and Staphylococcus aureus. These pathogens are associated with severe hospital and community infections difficult to treat due to resistance to multiple drugs. Moreover, light responses in Brucella abortus, an important animal and human pathogen, are also compiled. Evidence recovered so far indicates that light modulates aspects related to pathogenesis, persistence, and antibiotic susceptibility in these pathogens; such as motility, biofilm formation, iron uptake, tolerance to antibiotics, hemolysis and virulence. The pathogens elicit differential responses to light depending likely on their pathophysiology, ability to cause disease and characteristics of the host. The response to light is not restricted to discrete physiological traits but is global. In higher organisms, light provides spatial and temporal information. Then, it is crucial to understand what information light is providing in these bacterial pathogens. Our current hypothesis postulates that light serves as a signal that allows these pathogens to synchronize their behavior to the circadian rhythm of the host, to optimize infection. Advances on the molecular mechanism of light signal transduction and physiological responses to light, as well as in the relation between light and bacterial infection, would not only enlarge our understanding of bacterial pathogenesis but also could potentially provide alternative treatment options for infectious illnesses.
Collapse
Affiliation(s)
- Natalia Arana
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Bárbara Perez Mora
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Valentín Permingeat
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Rocío Giordano
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Malena Calderone
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Marisel Tuttobene
- Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Rosario, Argentina
| | - Sebastián Klinke
- Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, (C1405BWE) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Jimena Rinaldi
- Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, (C1405BWE) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Gabriela Müller
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina.
| | - María Alejandra Mussi
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina.
| |
Collapse
|
2
|
BfmRS encodes a regulatory system involved in light signal transduction modulating motility and desiccation tolerance in the human pathogen Acinetobacter baumannii. Sci Rep 2023; 13:175. [PMID: 36604484 PMCID: PMC9814549 DOI: 10.1038/s41598-022-26314-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 12/13/2022] [Indexed: 01/06/2023] Open
Abstract
We have previously shown that Acinetobacter baumannii as well as other relevant clinical bacterial pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa, perceive and respond to light at 37 °C, the normal temperature in mammal hosts. In this work, we present evidence indicating that the two-component system BfmRS transduces a light signal in A. baumannii at this temperature, showing selective involvement of the BfmR and BfmS components depending on the specific cellular process. In fact, both BfmR and BfmS participate in modulation of motility by light, while only BfmR is involved in light regulation of desiccation tolerance in this microorganism. Neither BfmR nor BfmS contain a photoreceptor domain and then most likely, the system is sensing light indirectly. Intriguingly, this system inhibits blsA expression at 37 °C, suggesting antagonistic functioning of both signaling systems. Furthermore, we present evidence indicating that the phosphorylatable form of BfmR represses motility. Overall, we provide experimental evidence on a new biological function of this multifaceted system that broadens our understanding of A. baumannii's physiology and responses to light.
Collapse
|
3
|
Abatedaga I, Perez Mora B, Tuttobene M, Müller G, Biancotti D, Borsarelli CD, Valle L, Mussi MA. Characterization of BLUF-photoreceptors present in Acinetobacter nosocomialis. PLoS One 2022; 17:e0254291. [PMID: 35442978 PMCID: PMC9020721 DOI: 10.1371/journal.pone.0254291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 03/01/2022] [Indexed: 11/18/2022] Open
Abstract
Acinetobacter nosocomialis is a Gram-negative opportunistic pathogen, whose ability to cause disease in humans is well recognized. Blue light has been shown to modulate important physiological traits related to persistence and virulence in this microorganism. In this work, we characterized the three Blue Light sensing Using FAD (BLUF) domain-containing proteins encoded in the A. nosocomialis genome, which account for the only canonical light sensors present in this microorganism. By focusing on a light-modulated bacterial process such as motility, the temperature dependence of light regulation was studied, as well as the expression pattern and spectroscopic characteristics of the different A. nosocomialis BLUFs. Our results show that the BLUF-containing proteins AnBLUF65 and AnBLUF46 encode active photoreceptors in the light-regulatory temperature range when expressed recombinantly. In fact, AnBLUF65 is an active photoreceptor in the temperature range from 15°C to 37°C, while AnBLUF46 between 15°C to 32°C, in vitro. In vivo, only the Acinetobacter baumannii BlsA’s ortholog AnBLUF65 was expressed in A. nosocomialis cells recovered from motility plates. Moreover, complementation assays showed that AnBLUF65 is able to mediate light regulation of motility in A. baumannii ΔblsA strain at 30°C, confirming its role as photoreceptor and in modulation of motility by light. Intra-protein interactions analyzed using 3D models built based on A. baumannii´s BlsA photoreceptor, show that hydrophobic/aromatic intra-protein interactions may contribute to the stability of dark/light- adapted states of the studied proteins, reinforcing the previous notion on the importance of these interactions in BLUF photoreceptors. Overall, the results presented here reveal the presence of BLUF photoreceptors in A. nosocomialis with idiosyncratic characteristics respect to the previously characterized A. baumannii’s BlsA, both regarding the photoactivity temperature-dependency as well as expression patterns, contributing thus to broaden our knowledge on the BLUF family.
Collapse
Affiliation(s)
- Inés Abatedaga
- Instituto de Bionanotecnología del NOA (INBIONATEC-CONICET), Universidad Nacional de Santiago del Estero (UNSE), Santiago del Estero, Argentina
| | - Bárbara Perez Mora
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Marisel Tuttobene
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Gabriela Müller
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Daiana Biancotti
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Claudio D. Borsarelli
- Instituto de Bionanotecnología del NOA (INBIONATEC-CONICET), Universidad Nacional de Santiago del Estero (UNSE), Santiago del Estero, Argentina
- Instituto de Ciencias Químicas (ICQ), Facultad de Agronomía y Agroindustrias (FAyA), UNSE, Santiago del Estero, Argentina
| | - Lorena Valle
- Instituto de Bionanotecnología del NOA (INBIONATEC-CONICET), Universidad Nacional de Santiago del Estero (UNSE), Santiago del Estero, Argentina
- Instituto de Ciencias Químicas (ICQ), Facultad de Agronomía y Agroindustrias (FAyA), UNSE, Santiago del Estero, Argentina
- * E-mail: (MAM); (LV)
| | - Maria A. Mussi
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI-CONICET), Universidad Nacional de Rosario (UNR), Rosario, Argentina
- * E-mail: (MAM); (LV)
| |
Collapse
|
4
|
Blue light directly modulates the quorum network in the human pathogen Acinetobacter baumannii. Sci Rep 2021; 11:13375. [PMID: 34183737 PMCID: PMC8239052 DOI: 10.1038/s41598-021-92845-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 06/14/2021] [Indexed: 01/02/2023] Open
Abstract
Quorum sensing modulates bacterial collective behaviors including biofilm formation, motility and virulence in the important human pathogen Acinetobacter baumannii. Disruption of quorum sensing has emerged as a promising strategy with important therapeutic potential. In this work, we show that light modulates the production of acyl-homoserine lactones (AHLs), which were produced in higher levels in the dark than under blue light at environmental temperatures, a response that depends on the AHL synthase, AbaI, and on the photoreceptor BlsA. BlsA interacts with the transcriptional regulator AbaR in the dark at environmental temperatures, inducing abaI expression. Under blue light, BlsA does not interact with AbaR, but induces expression of the lactonase aidA and quorum quenching, consistently with lack of motility at this condition. At temperatures found in warm-blooded hosts, the production of AHLs, quorum quenching as well as abaI and aidA expression were also modulated by light, though in this case higher levels of AHLs were detected under blue light than in the dark, in a BlsA-independent manner. Finally, AbaI reduces A. baumannii's ability to kill C. albicans only in the dark both at environmental as well as at temperatures found in warm-blooded hosts. The overall data indicate that light directly modulates quorum network in A. baumannii.
Collapse
|
5
|
Light Modulates Important Pathogenic Determinants and Virulence in ESKAPE Pathogens Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus. J Bacteriol 2021; 203:JB.00566-20. [PMID: 33288627 DOI: 10.1128/jb.00566-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/03/2020] [Indexed: 02/07/2023] Open
Abstract
Light sensing has been extensively characterized in the human pathogen Acinetobacter baumannii at environmental temperatures. However, the influence of light on the physiology and pathogenicity of human bacterial pathogens at temperatures found in warm-blooded hosts is still poorly understand. In this work, we show that Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa (ESKAPE) priority pathogens, which have been recognized by the WHO and the CDC as critical, can also sense and respond to light at temperatures found in human hosts. Most interestingly, in these pathogens, light modulates important pathogenicity determinants as well as virulence in an epithelial infection model, which could have implications in human infections. In fact, we found that alpha-toxin-dependent hemolysis, motility, and growth under iron-deprived conditions are modulated by light in S. aureus Light also regulates persistence, metabolism, and the ability to kill competitors in some of these microorganisms. Finally, light exerts a profound effect on the virulence of these pathogens in an epithelial infection model, although the response is not the same in the different species; virulence was enhanced by light in A. baumannii and S. aureus, while in A. nosocomialis and P. aeruginosa it was reduced. Neither the BlsA photoreceptor nor the type VI secretion system (T6SS) is involved in virulence modulation by light in A. baumannii Overall, this fundamental knowledge highlights the potential use of light to control pathogen virulence, either directly or by manipulating the light regulatory switch toward the lowest virulence/persistence configuration.IMPORTANCE Pathogenic bacteria are microorganisms capable of producing disease. Dangerous bacterial pathogens, such as Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, are responsible for serious intrahospital and community infections in humans. Therapeutics is often complicated due to resistance to multiple antibiotics, rendering them ineffective. In this work, we show that these pathogens sense natural light and respond to it by modulating aspects related to their ability to cause disease; in the presence of light, some of them become more aggressive, while others show an opposite response. Overall, we provide new understanding on the behavior of these pathogens, which could contribute to the control of infections caused by them. Since the response is distributed in diverse pathogens, this notion could prove a general concept.
Collapse
|
6
|
Chitrakar I, Iuliano JN, He Y, Woroniecka HA, Collado JT, Wint J, Walker SG, Tonge PJ, French JB. Structural Basis for the Regulation of Biofilm Formation and Iron Uptake in A. baumannii by the Blue-Light-Using Photoreceptor, BlsA. ACS Infect Dis 2020; 6:2592-2603. [PMID: 32926768 PMCID: PMC10035076 DOI: 10.1021/acsinfecdis.0c00156] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The opportunistic human pathogen, A. baumannii, senses and responds to light using the blue light sensing A (BlsA) photoreceptor protein. BlsA is a blue-light-using flavin adenine dinucleotide (BLUF) protein that is known to regulate a wide variety of cellular functions through interactions with different binding partners. Using immunoprecipitation of tagged BlsA in A. baumannii lysates, we observed a number of proteins that interact with BlsA, including several transcription factors. In addition to a known binding partner, the iron uptake regulator Fur, we identified the biofilm response regulator BfmR as a putative BlsA-binding partner. Using microscale thermophoresis, we determined that both BfmR and Fur bind to BlsA with nanomolar binding constants. To better understand how BlsA interacts with and regulates these transcription factors, we solved the X-ray crystal structures of BlsA in both a ground (dark) state and a photoactivated light state. Comparison of the light- and dark-state structures revealed that, upon photoactivation, the two α-helices comprising the variable domain of BlsA undergo a distinct conformational change. The flavin-binding site, however, remains largely unchanged from dark to light. These structures, along with docking studies of BlsA and Fur, reveal key mechanistic details about how BlsA propagates the photoactivation signal between protein domains and on to its binding partner. Taken together, our structural and biophysical data provide important insights into how BlsA controls signal transduction in A. baumannii and provides a likely mechanism for blue-light-dependent modulation of biofilm formation and iron uptake.
Collapse
Affiliation(s)
- Iva Chitrakar
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA, 11790
- Biochemistry and Structural Biology Program, Stony Brook University, Stony Brook, NY, USA, 11790
| | - James N. Iuliano
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA, 11790
| | - YongLe He
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA, 11790
| | | | | | - Jinelle Wint
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA, 11790
| | - Stephen G. Walker
- Department of Oral Biology and Pathology, Stony Brook University, Stony Brook, NY, USA, 11790
| | - Peter J. Tonge
- Biochemistry and Structural Biology Program, Stony Brook University, Stony Brook, NY, USA, 11790
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA, 11790
| | - Jarrod B. French
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA, 11790
- Biochemistry and Structural Biology Program, Stony Brook University, Stony Brook, NY, USA, 11790
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA, 11790
- The Hormel Institute, University of Minnesota, Austin, MN, 55912
- To whom correspondence should be addressed: Jarrod B. French: ; (507)437-9637
| |
Collapse
|