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Ermann Lundberg L, Pallabi Mishra P, Liu P, Forsberg MM, Sverremark-Ekström E, Grompone G, Håkansson S, Linninge C, Roos S. Bifidobacterium longum subsp. longum BG-L47 boosts growth and activity of Limosilactobacillus reuteri DSM 17938 and its extracellular membrane vesicles. Appl Environ Microbiol 2024; 90:e0024724. [PMID: 38888338 PMCID: PMC11267924 DOI: 10.1128/aem.00247-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 05/14/2024] [Indexed: 06/20/2024] Open
Abstract
The aim of this study was to identify a Bifidobacterium strain that improves the performance of Limosilactobacillus reuteri DSM 17938. Initial tests showed that Bifidobacterium longum subsp. longum strains boosted the growth of DSM 17938 during in vivo-like conditions. Further characterization revealed that one of the strains, BG-L47, had better bile and acid tolerance compared to BG-L48, as well as mucus adhesion compared to both BG-L48 and the control strain BB536. BG-L47 also had the capacity to metabolize a broad range of carbohydrates and sugar alcohols. Mapping of glycoside hydrolase (GH) genes of BG-L47 and BB536 revealed many GHs associated with plant-fiber utilization. However, BG-L47 had a broader phenotypic fiber utilization capacity. In addition, B. longum subsp. longum cells boosted the bioactivity of extracellular membrane vesicles (MV) produced by L. reuteri DSM 17938 during co-cultivation. Secreted 5'-nucleotidase (5'NT), an enzyme that converts AMP into the signal molecule adenosine, was increased in MV boosted by BG-L47. The MV exerted an improved antagonistic effect on the pain receptor transient receptor potential vanilloid 1 (TRPV1) and increased the expression of the immune development markers IL-6 and IL-1ß in a peripheral blood mononuclear cell (PBMC) model. Finally, the safety of BG-L47 was evaluated both by genome safety assessment and in a human safety study. Microbiota analysis showed that the treatment did not induce significant changes in the composition. In conclusion, B. longum subsp. longum BG-L47 has favorable physiological properties, can boost the in vitro activity of L. reuteri DSM 17938, and is safe for consumption, making it a candidate for further evaluation in probiotic studies. IMPORTANCE By using probiotics that contain a combination of strains with synergistic properties, the likelihood of achieving beneficial interactions with the host can increase. In this study, we first performed a broad screening of Bifidobacterium longum subsp. longum strains in terms of synergistic potential and physiological properties. We identified a superior strain, BG-L47, with favorable characteristics and potential to boost the activity of the known probiotic strain Limosilactobacillus reuteri DSM 17938. Furthermore, we demonstrated that BG-L47 is safe for consumption in a human randomized clinical study and by performing a genome safety assessment. This work illustrates that bacteria-bacteria interactions differ at the strain level and further provides a strategy for finding and selecting companion strains of probiotics.
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Affiliation(s)
- Ludwig Ermann Lundberg
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
- BioGaia, Stockholm, Sweden
| | - Punya Pallabi Mishra
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | | | - Manuel Mata Forsberg
- The Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Eva Sverremark-Ekström
- The Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | | | - Sebastian Håkansson
- BioGaia, Stockholm, Sweden
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Caroline Linninge
- BioGaia, Stockholm, Sweden
- Department of Food Technology, Engineering and Nutrition, Lund University, Lund, Sweden
| | - Stefan Roos
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
- BioGaia, Stockholm, Sweden
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2
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Prajapati A, Palva A, von Ossowski I, Krishnan V. The crystal structure of the N-terminal domain of the backbone pilin LrpA reveals a new closure-and-twist motion for assembling dynamic pili in Ligilactobacillus ruminis. Acta Crystallogr D Struct Biol 2024; 80:474-492. [PMID: 38935340 DOI: 10.1107/s2059798324005114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 05/30/2024] [Indexed: 06/28/2024] Open
Abstract
Sortase-dependent pili are long surface appendages that mediate attachment, colonization and biofilm formation in certain genera and species of Gram-positive bacteria. Ligilactobacillus ruminis is an autochthonous gut commensal that relies on sortase-dependent LrpCBA pili for host adherence and persistence. X-ray crystal structure snapshots of the backbone pilin LrpA were captured in two atypical bent conformations leading to a zigzag morphology in the LrpCBA pilus structure. Small-angle X-ray scattering and structural analysis revealed that LrpA also adopts the typical linear conformation, resulting in an elongated pilus morphology. Various conformational analyses and biophysical experiments helped to demonstrate that a hinge region located at the end of the flexible N-terminal domain of LrpA facilitates a new closure-and-twist motion for assembling dynamic pili during the assembly process and host attachment. Further, the incongruent combination of flexible domain-driven conformational dynamics and rigid isopeptide bond-driven stability observed in the LrpCBA pilus might also extend to the sortase-dependent pili of other bacteria colonizing a host.
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Affiliation(s)
- Amar Prajapati
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR, Biotech Science Cluster, Faridabad 121 001, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Vengadesan Krishnan
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR, Biotech Science Cluster, Faridabad 121 001, India
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3
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Bin Hafeez A, Pełka K, Worobo R, Szweda P. In Silico Safety Assessment of Bacillus Isolated from Polish Bee Pollen and Bee Bread as Novel Probiotic Candidates. Int J Mol Sci 2024; 25:666. [PMID: 38203838 PMCID: PMC10780176 DOI: 10.3390/ijms25010666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/23/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
Bacillus species isolated from Polish bee pollen (BP) and bee bread (BB) were characterized for in silico probiotic and safety attributes. A probiogenomics approach was used, and in-depth genomic analysis was performed using a wide array of bioinformatics tools to investigate the presence of virulence and antibiotic resistance properties, mobile genetic elements, and secondary metabolites. Functional annotation and Carbohydrate-Active enZYmes (CAZYme) profiling revealed the presence of genes and a repertoire of probiotics properties promoting enzymes. The isolates BB10.1, BP20.15 (isolated from bee bread), and PY2.3 (isolated from bee pollen) genome mining revealed the presence of several genes encoding acid, heat, cold, and other stress tolerance mechanisms, adhesion proteins required to survive and colonize harsh gastrointestinal environments, enzymes involved in the metabolism of dietary molecules, antioxidant activity, and genes associated with the synthesis of vitamins. In addition, genes responsible for the production of biogenic amines (BAs) and D-/L-lactate, hemolytic activity, and other toxic compounds were also analyzed. Pan-genome analyses were performed with 180 Bacillus subtilis and 204 Bacillus velezensis genomes to mine for any novel genes present in the genomes of our isolates. Moreover, all three isolates also consisted of gene clusters encoding secondary metabolites.
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Affiliation(s)
- Ahmer Bin Hafeez
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdańsk University of Technology, Ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland; (A.B.H.); (K.P.)
| | - Karolina Pełka
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdańsk University of Technology, Ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland; (A.B.H.); (K.P.)
| | - Randy Worobo
- Department of Food Science, Cornell University, Ithaca, NY 14853, USA;
| | - Piotr Szweda
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdańsk University of Technology, Ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland; (A.B.H.); (K.P.)
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4
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Exploring Bacterial Attributes That Underpin Symbiont Life in the Monogastric Gut. Appl Environ Microbiol 2022; 88:e0112822. [PMID: 36036591 PMCID: PMC9499014 DOI: 10.1128/aem.01128-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The large bowel of monogastric animals, such as that of humans, is home to a microbial community (microbiota) composed of a diversity of mostly bacterial species. Interrelationships between the microbiota as an entity and the host are complex and lifelong and are characteristic of a symbiosis. The relationships may be disrupted in association with disease, resulting in dysbiosis. Modifications to the microbiota to correct dysbiosis require knowledge of the fundamental mechanisms by which symbionts inhabit the gut. This review aims to summarize aspects of niche fitness of bacterial species that inhabit the monogastric gut, especially of humans, and to indicate the research path by which progress can be made in exploring bacterial attributes that underpin symbiont life in the gut.
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Gorreja F, Walker WA. The potential role of adherence factors in probiotic function in the gastrointestinal tract of adults and pediatrics: a narrative review of experimental and human studies. Gut Microbes 2022; 14:2149214. [PMID: 36469568 PMCID: PMC9728474 DOI: 10.1080/19490976.2022.2149214] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
Numerous studies point to the important role of probiotic bacteria in gastrointestinal health. Probiotics act through mechanisms affecting enteric pathogens, epithelial barrier function, immune signaling, and conditioning of indigenous microbiota. Once administered, probiotics reach the gastrointestinal tract and interact with the host through bacterial surface molecules, here called adhesion factors, which are either strain- or specie-specific. Probiotic adhesion, through structural adhesion factors, is a mechanism that facilitates persistence within the gastrointestinal tract and triggers the initial host responses. Thus, an understanding of specific probiotic adhesion mechanisms could predict how specific probiotic strains elicit benefits and the potential of adherence factors as a proxy to predict probiotic function. This review summarizes the present understanding of probiotic adherence in the gastrointestinal tract. It highlights the bacterial adhesion structure types, their molecular communication with the host and the consequent impact on intestinal diseases in both adult and pediatric populations. Finally, we discuss knockout/isolation studies as direct evidence for adhesion factors conferring anti-inflammatory and pathogen inhibition properties to a probiotic.What is known: Probiotics can be used to treat clinical conditions.Probiotics improve dysbiosis and symptoms.Clinical trials may not confirm in vitro and animal studies.What is new: Adhesion structures may be important for probiotic function.Need to systematically determine physical characteristics of probiotics before selecting for clinical trials.Probiotics may be genetically engineered to add to clinical efficacy.
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Affiliation(s)
- Frida Gorreja
- Department of Microbiology and Immunology, Institute for Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Nutrition-Gut-Brain Interactions Research Centre, School of Medical Sciences, Örebro University, Örebro, Sweden
| | - W. Allan Walker
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Harvard Medical School, Boston, Massachusetts, USA
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6
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Prajapati A, Palva A, von Ossowski I, Krishnan V. LrpCBA pilus proteins of gut-dwelling Ligilactobacillus ruminis: crystallization and X-ray diffraction analysis. Acta Crystallogr F Struct Biol Commun 2021; 77:238-245. [PMID: 34341189 PMCID: PMC8329715 DOI: 10.1107/s2053230x21007263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/13/2021] [Indexed: 11/10/2022] Open
Abstract
Adhesion to host surfaces for bacterial survival and colonization involves a variety of molecular mechanisms. Ligilactobacillus ruminis, a strict anaerobe and gut autochthonous (indigenous) commensal, relies on sortase-dependent pili (LrpCBA) for adherence to the intestinal inner walls, thereby withstanding luminal content flow. Here, the LrpCBA pilus is a promiscuous binder to gut collagen, fibronectin and epithelial cells. Structurally, the LrpCBA pilus displays a representative hetero-oligomeric arrangement and consists of three types of pilin subunit, each with its own location and function, i.e. tip LrpC for adhesion, basal LrpB for anchoring and backbone LrpA for length. To provide further structural insights into the assembly, anchoring and functional mechanisms of sortase-dependent pili, each of the L. ruminis pilus proteins was produced recombinantly for crystallization and X-ray diffraction analysis. Crystals of LrpC, LrpB, LrpA and truncated LrpA generated by limited proteolysis were obtained and diffracted to resolutions of 3.0, 1.5, 2.2 and 1.4 Å, respectively. Anomalous data were also collected from crystals of selenomethionine-substituted LrpC and an iodide derivative of truncated LrpA. Successful strategies for protein production, crystallization and derivatization are reported.
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Affiliation(s)
- Amar Prajapati
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 121 001, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Vengadesan Krishnan
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 121 001, India
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7
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Exploiting pilus-mediated bacteria-host interactions for health benefits. Mol Aspects Med 2021; 81:100998. [PMID: 34294411 DOI: 10.1016/j.mam.2021.100998] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/30/2021] [Accepted: 07/16/2021] [Indexed: 02/06/2023]
Abstract
Surface pili (or fimbriae) are an important but conspicuous adaptation of several genera and species of Gram-negative and Gram-positive bacteria. These long and non-flagellar multi-subunit adhesins mediate the initial contact that a bacterium has with a host or environment, and thus have come to be regarded as a key colonization factor for virulence activity in pathogens or niche adaptation in commensals. Pili in pathogenic bacteria are well recognized for their roles in the adhesion to host cells, colonization of tissues, and establishment of infection. As an 'anti-adhesive' ploy, targeting pilus-mediated attachment for disruption has become a potentially effective alternative to using antibiotics. In this review, we give a description of the several structurally distinct bacterial pilus types thus far characterized, and as well offer details about the intricacy of their individual structure, assembly, and function. With a molecular understanding of pilus biogenesis and pilus-mediated host interactions also provided, we go on to describe some of the emerging new approaches and compounds that have been recently developed to prevent the adhesion, colonization, and infection of piliated bacterial pathogens.
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8
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Susmitha A, Bajaj H, Madhavan Nampoothiri K. The divergent roles of sortase in the biology of Gram-positive bacteria. ACTA ACUST UNITED AC 2021; 7:100055. [PMID: 34195501 PMCID: PMC8225981 DOI: 10.1016/j.tcsw.2021.100055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 12/16/2022]
Abstract
The bacterial cell wall contains numerous surface-exposed proteins, which are covalently anchored and assembled by a sortase family of transpeptidase enzymes. The sortase are cysteine transpeptidases that catalyzes the covalent attachment of surface protein to the cell wall peptidoglycan. Among the reported six classes of sortases, each distinct class of sortase plays a unique biological role in anchoring a variety of surface proteins to the peptidoglycan of both pathogenic and non-pathogenic Gram-positive bacteria. Sortases not only exhibit virulence and pathogenesis properties to host cells, but also possess a significant role in gut retention and immunomodulation in probiotic microbes. The two main distinct functions are to attach proteins directly to the cell wall or assemble pili on the microbial surface. This review provides a compendium of the distribution of different classes of sortases present in both pathogenic and non-pathogenic Gram-positive bacteria and also the noteworthy role played by them in bacterial cell wall assembly which enables each microbe to effectively interact with its environment.
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Affiliation(s)
- Aliyath Susmitha
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Harsha Bajaj
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India
| | - Kesavan Madhavan Nampoothiri
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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9
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Zhang F, Dai J, Chen T. Role of Lactobacillus in Female Infertility Via Modulating Sperm Agglutination and Immobilization. Front Cell Infect Microbiol 2021; 10:620529. [PMID: 33569356 PMCID: PMC7868545 DOI: 10.3389/fcimb.2020.620529] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 12/08/2020] [Indexed: 12/13/2022] Open
Abstract
Infertility has become a common problem in recent decades. The pathogenesis of infertility is variable, but microbiological factors account for a large proportion of it. Dysbiosis of vaginal microbiota is reportedly associated with female infertility, but the influence of normal vaginal microbiota on infertility is unclear. In this review, we summarize the physiological characteristics of the vaginal tract and vaginal microbiota communities. We mainly focus on the bacterial adherence of vaginal Lactobacillus species. Given that the adherent effect plays a crucial role in the colonization of bacteria, we hypothesize that the adherent effect of vaginal Lactobacillus may also influence the fertility of the host. We also analyze the agglutination and immobilization effects of other bacteria, especially Escherichia coli, on ejaculated spermatozoa, and speculate on the possible effects of normal vaginal microbiota on female fertility.
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Affiliation(s)
- Fenghao Zhang
- Institute of Translational Medicine & School of Life Sciences, Nanchang University, Nanchang, China
| | - Jie Dai
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Renal Cancer and Melanoma, Peking University Cancer Hospital and Institute, Beijing, China
| | - Tingtao Chen
- Institute of Translational Medicine & School of Life Sciences, Nanchang University, Nanchang, China
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10
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Dos Santos Morais R, El-Kirat-Chatel S, Burgain J, Simard B, Barrau S, Paris C, Borges F, Gaiani C. A Fast, Efficient and Easy to Implement Method to Purify Bacterial Pili From Lacticaseibacillus rhamnosus GG Based on Multimodal Chromatography. Front Microbiol 2020; 11:609880. [PMID: 33391233 PMCID: PMC7775309 DOI: 10.3389/fmicb.2020.609880] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/24/2020] [Indexed: 01/02/2023] Open
Abstract
Pili are polymeric proteins located at the cell surface of bacteria. These filamentous proteins play a pivotal role in bacterial adhesion with the surrounding environment. They are found both in Gram-negative and Gram-positive bacteria but differ in their structural organization. Purifying these high molecular weight proteins is challenging and has certainly slowed down their characterization. Here, we propose a chromatography-based protocol, mainly relying on multimodal chromatography (core bead technology using Capto Core 700 resin), to purify sortase-dependent SpaCBA pili from the probiotic strain Lacticaseibacillus rhamnosus GG (LGG). Contrary to previously published methods, this purification protocol does not require specific antibodies nor complex laboratory equipment, including for the multimodal chromatography step, and provides high degree of protein purity. No other proteins were detectable by SDS-PAGE and the 260/280 nm ratio (∼0.6) of the UV spectrum confirmed the absence of any other co-purified macromolecules. One can obtain ∼50 μg of purified pili, starting from 1 L culture at OD600nm ≈ 1, in 2–3 working days. This simple protocol could be useful to numerous laboratories to purify pili from LGG easily. Therefore, the present work should boost specific studies dedicated to LGG SpaCBA pili and the characterization of the interactions occurring with their protein partners at the molecular level. Moreover, this straightforward purification process might be extended to the purification of sortase-dependant pili from other Gram-positive bacteria.
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Affiliation(s)
| | - Sofiane El-Kirat-Chatel
- Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement (LCPME), UMR 7564, CNRS-Université de Lorraine, Nancy, France
| | - Jennifer Burgain
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Nancy, France
| | - Blandine Simard
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Nancy, France
| | - Sarah Barrau
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Nancy, France
| | - Cédric Paris
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Nancy, France
| | - Frédéric Borges
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Nancy, France
| | - Claire Gaiani
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Nancy, France.,Institut Universitaire de France, Parris, France
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Megta AK, Pratap S, Kant A, Palva A, von Ossowski I, Krishnan V. Crystal structure of the atypically adhesive SpaB basal pilus subunit: Mechanistic insights about its incorporation in lactobacillar SpaCBA pili. Curr Res Struct Biol 2020; 2:229-238. [PMID: 34235482 PMCID: PMC8244301 DOI: 10.1016/j.crstbi.2020.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 02/07/2023] Open
Abstract
To successfully colonize a host or environment, certain genera and species of Gram-positive bacteria have evolved to utilize the so-called sortase-dependent pilus, a long multi-subunit and non-flagellar surface adhesin. One example of this is Lactobacillus rhamnosus GG, a gut-adapted probiotic strain that produces SpaCBA pili. These structures are covalent hetero-oligomers built from three types of pilin subunit, each with a specific location and function (i.e., backbone SpaA for length, tip SpaC for adhesion, and basal SpaB for anchoring). Functionally, the SpaCBA pilus exhibits a promiscuous affinity for components on intestinal surfaces (e.g., mucus, collagen, and epithelial cells), which is largely attributed to the SpaC subunit. Then again, the basal SpaB pilin, in addition to acting as the terminal subunit during pilus assembly, displays an out of character mucoadhesive function. To address the structural basis of this unusual dual functionality, we reveal the 2.39 Å resolution crystal structure of SpaB. SpaB consists of one immunoglobulin-like CnaB domain and contains a putative intermolecular isopeptide bond-linking lysine and internal isopeptide bond-asparagine in an FPKN pilin motif within the C-terminal end. Remarkably, we found that a C-terminal stretch of positively charged lysine and arginine residues likely accounts for the atypical mucoadhesiveness of SpaB. Although harboring an autocatalytic triad of residues for a potential internal isopeptide interaction, the SpaB crystal structure lacked the visible electron density for intact bond formation, yet its presence was subsequently confirmed by mass spectral analysis. Finally, we propose a structural model that captures the exclusive basal positioning of SpaB in the SpaCBA pilus.
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Key Words
- ABC, ammonium bicarbonate
- ACN, acetonitrile
- Cell-wall anchoring
- Cna, collagen adhesin
- ECM, extracellular matrix
- Ig, immunoglobulin
- Lactobacillus rhamnosus GG
- MD, molecular dynamics
- MS, mass spectrometry
- Mucus adhesion
- PDB, Protein Data Bank
- PEG, polyethylene glycol
- Probiotic
- Sortase-dependent SpaCBA pili
- SpaB basal pilin
- rmsd, root mean square deviation
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Affiliation(s)
- Abhin Kumar Megta
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India.,School of Biotechnology, KIIT University, Odisha, 751024, India
| | - Shivendra Pratap
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India
| | - Abhiruchi Kant
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India.,Department of Biotechnology, Manipal University, Karnataka, 576104, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, FIN-00014, Finland
| | - Ingemar von Ossowski
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, FIN-00014, Finland
| | - Vengadesan Krishnan
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India
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Zhou B, Albarracin L, Indo Y, Arce L, Masumizu Y, Tomokiyo M, Islam MA, Garcia-Castillo V, Ikeda-Ohtsubo W, Nochi T, Morita H, Takahashi H, Kurata S, Villena J, Kitazawa H. Selection of Immunobiotic Ligilactobacillus salivarius Strains from the Intestinal Tract of Wakame-Fed Pigs: Functional and Genomic Studies. Microorganisms 2020; 8:microorganisms8111659. [PMID: 33114778 PMCID: PMC7716343 DOI: 10.3390/microorganisms8111659] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 12/11/2022] Open
Abstract
In this article, Ligilactobacillus salivarius FFIG strains, isolated from the intestinal tract of wakame-fed pigs, are characterized according to their potential probiotic properties. Strains were evaluated by studying their interaction with porcine intestinal epithelial (PIE) cells in terms of their ability to regulate toll-like receptor (TLR)-3- or TLR4-mediated innate immune responses, as well as by assessing their adhesion capabilities to porcine epithelial cells and mucins. These functional studies were complemented with comparative genomic evaluations using the complete genome sequences of porcine L. salivarius strains selected from subgroups that demonstrated different “immune” and “adhesion” phenotypes. We found that their immunomodulatory and adhesion capabilities are a strain-dependent characteristic. Our analysis indicated that the differential immunomodulatory and adhesive activities of FFIG strains would be dependent on the combination of several surface structures acting simultaneously, which include peptidoglycan, exopolysaccharides, lipoteichoic acid, and adhesins. Of note, our results indicate that there is no correlation between the immunomodulatory capacity of the strains with their adhesion ability to mucins and epithelial cells. Therefore, in the selection of strains destined to colonize the intestinal mucosa and modulate the immunity of the host, both properties must be adequately evaluated. Interestingly, we showed that L. salivarius FFIG58 functionally modulated the innate immune responses triggered by TLR3 and TLR4 activation in PIE cells and efficiently adhered to these cells. Moreover, the FFIG58 strain was capable of reducing rotavirus replication in PIE cells. Therefore, L. salivarius FFIG58 is a good candidate for further in vivo studying the protective effect of lactobacilli against intestinal infections in the porcine host. We also reported and analyzed, for the first time, the complete genome of several L. salivarius strains that were isolated from the intestine of pigs after the selective pressure of feeding the animals with wakame. Further genomic analysis could be of value to reveal the metabolic characteristics and potential of the FFIG strains in general and of the FFIG58 strain, in particular, relating to wakame by-products assimilation.
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Affiliation(s)
- Binghui Zhou
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
| | - Leonardo Albarracin
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Laboratory of Immunobiotechnology, Reference Centre for Lactobacilli (CERELA-CONICET), Tucuman 4000, Argentina
- Scientific Computing Laboratory, Computer Science Department, Faculty of Exact Sciences and Technology, National University of Tucuman, Tucuman 4000, Argentina
| | - Yuhki Indo
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
| | - Lorena Arce
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Infection Biology Laboratory, INSIBIO-CONICET, Faculty of Medicine, University of Tucuman, Tucuman 4000, Argentina
| | - Yuki Masumizu
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
| | - Mikado Tomokiyo
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
| | - Md. Aminul Islam
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
- Department of Medicine, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Valeria Garcia-Castillo
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Laboratory of Immunobiotechnology, Reference Centre for Lactobacilli (CERELA-CONICET), Tucuman 4000, Argentina
| | - Wakako Ikeda-Ohtsubo
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
| | - Tomonori Nochi
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
- Laboratory of Functional Morphology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
| | - Hidetoshi Morita
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan;
| | - Hideki Takahashi
- Laboratory of Plant Pathology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
- Plant Immunology Unit, International Education and Research Center for Food and Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
| | - Shoichiro Kurata
- Laboratory of Molecular Genetics, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8572, Japan;
| | - Julio Villena
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Laboratory of Immunobiotechnology, Reference Centre for Lactobacilli (CERELA-CONICET), Tucuman 4000, Argentina
- Correspondence: (J.V.); (H.K.)
| | - Haruki Kitazawa
- Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (B.Z.); (L.A.); (Y.I.); (L.A.); (Y.M.); (M.T.); (M.A.I.); (V.G.-C.); (W.I.-O.)
- Livestock Immunology Unit, International Education and Research Center for Food Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan;
- Correspondence: (J.V.); (H.K.)
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Kant A, Palva A, von Ossowski I, Krishnan V. Crystal structure of lactobacillar SpaC reveals an atypical five-domain pilus tip adhesin: Exposing its substrate-binding and assembly in SpaCBA pili. J Struct Biol 2020; 211:107571. [PMID: 32653644 DOI: 10.1016/j.jsb.2020.107571] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 06/23/2020] [Accepted: 07/02/2020] [Indexed: 12/11/2022]
Abstract
Adhesion to cell surfaces is an essential and early prerequisite for successful host colonization by bacteria, and in most instances involves the specificities of various adhesins. Among bacterial Gram-positives, some genera and species mediate attachment to host cells by using long non-flagellar appendages called sortase-dependent pili. A case in point is the beneficial Lactobacillus rhamnosus GG gut-adapted strain that produces the so-called SpaCBA pilus, a structure noted for its promiscuous binding to intestinal mucus and collagen. Structurally, SpaCBA pili are heteropolymers of three different pilin-protein subunits, each with its own location and function in the pilus: backbone SpaA for length, basal SpaB for anchoring, and tip SpaC for adhesion. Previously, we solved the SpaA tertiary structure by X-ray crystallography and also reported on the crystallization of SpaB and SpaC. Here, we reveal the full-length high-resolution (1.9 Å) crystal structure of SpaC, a first for a sortase-dependent pilus-bearing commensal. The SpaC structure, unlike the representative four-domain architecture of other Gram-positive tip pilins, espouses an atypically longer five-domain arrangement that includes N-terminal 'binding' and C-terminal 'stalk' regions of two and three domains, respectively. With the prospect of establishing new mechanistic insights, we provide a structural basis for the multi-substrate binding nature of SpaC, as well as a structural model that reconciles its exclusive localization at the SpaCBA pilus tip.
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Affiliation(s)
- Abhiruchi Kant
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 122016, India; Department of Biotechnology, Manipal University, Karnataka 576104, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki FIN-00014, Finland
| | - Ingemar von Ossowski
- Department of Veterinary Biosciences, University of Helsinki, Helsinki FIN-00014, Finland
| | - Vengadesan Krishnan
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad 122016, India.
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Pratap S, Megta AK, Krishnan V. Sortases from a Probiotic Lactobacillus rhamnosus GG: Cloning, Expression, Purification, Crystallization and Preliminary X-Ray Diffraction Study. CRYSTALLOGR REP+ 2020. [DOI: 10.1134/s1063774519070162] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Kumar Megta A, Palva A, von Ossowski I, Krishnan V. SpaB, an atypically adhesive basal pilin from the lactobacillar SpaCBA pilus: crystallization and X-ray diffraction analysis. Acta Crystallogr F Struct Biol Commun 2019; 75:731-737. [PMID: 31797814 PMCID: PMC6891582 DOI: 10.1107/s2053230x19015358] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 11/13/2019] [Indexed: 02/06/2023] Open
Abstract
The SpaB pilin is recognized as the basal subunit of the sortase-dependent SpaCBA pilus, which is known to be produced by the Gram-positive Lactobacillus rhamnosus GG, a gut-adapted commensal advocated to have health benefits. Despite seeming to function as an archetypal basal pilin by serving as the terminal subunit in pilus assembly, SpaB also assumes an atypical role as a mucoadhesive protein. To shed light on the structural factors that contribute to this dual functional behaviour, a recombinant form of the L. rhamnosus GG SpaB pilin was produced and purified for crystallization and X-ray diffraction experiments. The crystallization of SpaB remained particularly challenging until the implementation of a three-pronged crystallization approach involving C-terminal tail truncation, surface lysine methylation and magnesium additives. Ultimately, hexagonal crystals of SpaB were produced and were able to diffract to a resolution of 2.4 Å. This crystal form belonged to space group P6522 or P6122, with unit-cell parameters a = b = 51.53, c = 408.22 Å, α = β = 90.0, γ = 120.0°. Obtaining an interpretable electron-density map via single-wavelength anomalous diffraction (SAD) using iodide-derivative data sets did not succeed owing to the weak anomalous signal. As an alternative, attempts to provide phases by molecular replacement using the iodide-SAD data from SpaB and a collection of distant homology models (<28% sequence identity) are in progress.
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Affiliation(s)
- Abhin Kumar Megta
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India
- School of Biotechnology, KIIT University, Odisha 751 024, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Vengadesan Krishnan
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India
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16
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Megta AK, Mishra AK, Palva A, von Ossowski I, Krishnan V. Crystal structure of basal pilin SpaE reveals the molecular basis of its incorporation in the lactobacillar SpaFED pilus. J Struct Biol 2019; 207:74-84. [PMID: 31026587 DOI: 10.1016/j.jsb.2019.04.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/15/2019] [Accepted: 04/23/2019] [Indexed: 11/16/2022]
Abstract
For some Gram-positive genera and species, the long-extended and adhesive sortase-dependent pilus plays an essential role during host colonization, biofilm formation, and immune modulation. Lactobacillus rhamnosus GG is a gut-adapted commensal strain that harbors the operonic genes for the SpaCBA and SpaFED pili, both being comprised of three different protein subunits termed the backbone, tip, and basal pilins. Crystal structures of the backbone pilins (SpaA and SpaD) have recently been solved, and here we describe the high-resolution (1.5 Å) structural determination of the SpaE basal pilin. SpaE consists of two immunoglobulin-like CnaB domains, with each displaying a spontaneously formed internal isopeptide bond, though apparently slow forming in the N-terminal domain. Remarkably, SpaE contains an atypically lengthy unstructured C-terminal tail, along with an YPKN pilin motif peptide, which is normally reserved for backbone subunits. Based on our analysis of the crystal structure data, we provide a molecular model for the basal positioning of the SpaE pilin within the SpaFED pilus.
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Affiliation(s)
- Abhin Kumar Megta
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India; School of Biotechnology, KIIT University, Odisha 751024, India
| | - Arjun K Mishra
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Vengadesan Krishnan
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana 121 001, India.
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Dai X, Böker A, Glebe U. Broadening the scope of sortagging. RSC Adv 2019; 9:4700-4721. [PMID: 35514663 PMCID: PMC9060782 DOI: 10.1039/c8ra06705h] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 01/31/2019] [Indexed: 01/20/2023] Open
Abstract
Sortases are enzymes occurring in the cell wall of Gram-positive bacteria. Sortase A (SrtA), the best studied sortase class, plays a key role in anchoring surface proteins with the recognition sequence LPXTG covalently to oligoglycine units of the bacterial cell wall. This unique transpeptidase activity renders SrtA attractive for various purposes and motivated researchers to study multiple in vivo and in vitro ligations in the last decades. This ligation technique is known as sortase-mediated ligation (SML) or sortagging and developed to a frequently used method in basic research. The advantages are manifold: extremely high substrate specificity, simple access to substrates and enzyme, robust nature and easy handling of sortase A. In addition to the ligation of two proteins or peptides, early studies already included at least one artificial (peptide equipped) substrate into sortagging reactions - which demonstrates the versatility and broad applicability of SML. Thus, SML is not only a biology-related technique, but has found prominence as a major interdisciplinary research tool. In this review, we provide an overview about the use of sortase A in interdisciplinary research, mainly for protein modification, synthesis of protein-polymer conjugates and immobilization of proteins on surfaces.
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Affiliation(s)
- Xiaolin Dai
- Fraunhofer Institute for Applied Polymer Research IAP Geiselbergstr. 69 14476 Potsdam-Golm Germany
- Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam 14476 Potsdam-Golm Germany
| | - Alexander Böker
- Fraunhofer Institute for Applied Polymer Research IAP Geiselbergstr. 69 14476 Potsdam-Golm Germany
- Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam 14476 Potsdam-Golm Germany
| | - Ulrich Glebe
- Fraunhofer Institute for Applied Polymer Research IAP Geiselbergstr. 69 14476 Potsdam-Golm Germany
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Chaurasia P, Pratap S, Palva A, von Ossowski I, Krishnan V. Bent conformation of a backbone pilin N-terminal domain supports a three-stage pilus assembly mechanism. Commun Biol 2018; 1:94. [PMID: 30271975 PMCID: PMC6123636 DOI: 10.1038/s42003-018-0100-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/21/2018] [Indexed: 12/31/2022] Open
Abstract
Effective colonization of host cells by some Gram-positive bacteria often involves using lengthy, adhesive macromolecular structures called sortase-dependent pili. Among commensals, the gut-adapted Lactobacillus rhamnosus GG strain encodes the operons for two varieties of these pili (SpaCBA and SpaFED), with each structure consisting of backbone, tip, and basal pilin subunits. Although the tertiary structure was recently solved for the backbone subunit (SpaA) of the SpaCBA pilus, no structural information exists for its counterpart in the SpaFED pilus. Here, we report several crystal structures for the SpaD backbone pilin, two of which capture the N-terminal domain in either the closed (linear) or open (bent) conformation. To our knowledge, this is the first observation of the bent conformation in Gram-positive pilin structures. Based on this bent conformation, we suggest a three-stage model, which we call the expose-ligate-seal mechanism, for the docking and assembly of backbone pilins into the sortase-dependent pilus. Priyanka Chaurasia et al. report crystal structures of the SpaD backbone pilin from a gut-adapted bacteria, Lactobacillus rhamnosus. The observed bent conformation of the N-terminal domain has not been seen in other Gram-positive pilin structures.
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Affiliation(s)
- Priyanka Chaurasia
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India.,Department of Biotechnology, Manipal University, Manipal, Karnataka, 576104, India
| | - Shivendra Pratap
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, FIN-00014, Helsinki, Finland
| | - Ingemar von Ossowski
- Department of Veterinary Biosciences, University of Helsinki, FIN-00014, Helsinki, Finland
| | - Vengadesan Krishnan
- Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India.
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