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Takada H, Katoh T, Sakanaka M, Odamaki T, Katayama T. GH20 and GH84 β-N-acetylglucosaminidases with different linkage specificities underpin mucin O-glycan breakdown capability of Bifidobacterium bifidum. J Biol Chem 2023:104781. [PMID: 37146969 DOI: 10.1016/j.jbc.2023.104781] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 04/28/2023] [Accepted: 04/29/2023] [Indexed: 05/07/2023] Open
Abstract
Intestinal mucus layers mediate symbiosis and dysbiosis of host-microbe interactions. These interactions are influenced by the mucin O-glycan degrading ability of several gut microbes. The identities and prevalence of many glycoside hydrolyses (GHs) involved in microbial mucin O-glycan breakdown have been previously reported; however, the exact mechanisms and extent to which these GHs are dedicated to mucin O-glycan degradation pathways warrant further research. Here, using Bifidobacterium bifidum as a model mucinolytic bacterium, we revealed that two β-N-acetylglucosaminidases belonging to the GH20 (BbhI) and GH84 (BbhIV) families play important roles in mucin O-glycan degradation. Using substrate specificity analysis of natural oligosaccharides and O-glycomic analysis of porcine gastric mucin (PGM) incubated with purified enzymes or B. bifidum carrying bbhI and/or bbhIV mutations, we showed that BbhI and BbhIV are highly specific for β-(1→3)- and β-(1→6)-GlcNAc linkages of mucin core structures, respectively. Interestingly, we found that efficient hydrolysis of the β-(1→3)-linkage by BbhI of the mucin core 4 structure [GlcNAcβ1-3(GlcNAcβ1-6)GalNAcα-O-Thr] required prior removal of the β-(1→6)-GlcNAc linkage by BbhIV. Consistent with this, inactivation of bbhIV markedly decreased the ability of B. bifidum to release GlcNAc from PGM. When combined with a bbhI mutation, we observed that the growth of the strain on PGM was reduced. Finally, phylogenetic analysis suggests that GH84 members may have gained diversified functions through microbe-microbe and host-microbe horizontal gene transfer events. Taken together, these data strongly suggest GH84 family members in host glycan breakdown.
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Affiliation(s)
- Hiromi Takada
- Graduate School of Biostudies, Kyoto University, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Toshihiko Katoh
- Graduate School of Biostudies, Kyoto University, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Mikiyasu Sakanaka
- Graduate School of Biostudies, Kyoto University, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Toshitaka Odamaki
- Graduate School of Biostudies, Kyoto University, Sakyo-Ku, Kyoto 606-8502, Japan; Next Generation Science Institute, Morinaga Milk Industry Co. Ltd., Zama, Kanagawa 252-8583, Japan
| | - Takane Katayama
- Graduate School of Biostudies, Kyoto University, Sakyo-Ku, Kyoto 606-8502, Japan.
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The Gene Expression Profile Differs in Growth Phases of the Bifidobacterium Longum Culture. Microorganisms 2022; 10:microorganisms10081683. [PMID: 36014100 PMCID: PMC9415070 DOI: 10.3390/microorganisms10081683] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 08/16/2022] [Accepted: 08/19/2022] [Indexed: 11/21/2022] Open
Abstract
To date, transcriptomics have been widely and successfully employed to study gene expression in different cell growth phases of bacteria. Since bifidobacteria represent a major component of the gut microbiota of a healthy human that is associated with numerous health benefits for the host, it is important to study them using transcriptomics. In this study, we applied the RNA-Seq technique to study global gene expression of B. longum at different growth phases in order to better understand the response of bifidobacterial cells to the specific conditions of the human gut. We have shown that in the lag phase, ABC transporters, whose function may be linked to active substrate utilization, are increasingly expressed due to preparation for cell division. In the exponential phase, the functions of activated genes include synthesis of amino acids (alanine and arginine), energy metabolism (glycolysis/gluconeogenesis and nitrogen metabolism), and translation, all of which promote active cell division, leading to exponential growth of the culture. In the stationary phase, we observed a decrease in the expression of genes involved in the control of the rate of cell division and an increase in the expression of genes involved in defense-related metabolic pathways. We surmise that the latter ensures cell survival in the nutrient-deprived conditions of the stationary growth phase.
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3
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Wang H, An J, Fan C, Zhai Z, Zhang H, Hao Y. Transcriptome analysis revealed growth phase-associated changes of a centenarian-originated probiotic Bifidobacterium animalis subsp. lactis A6. BMC Microbiol 2022; 22:61. [PMID: 35209838 PMCID: PMC8876546 DOI: 10.1186/s12866-022-02474-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 02/07/2022] [Indexed: 12/14/2022] Open
Abstract
Background The physiology and application characteristics of probiotics are closely associated with the growth phase. Bifidobacterium animalis subsp. lactis A6 is a promising probiotic strain isolated from the feces of a healthy centenarian in China. In this study, RNA-seq was carried out to investigate the metabolic mechanism between the exponential and the stationary phase in B. lactis A6. Results Differential expression analysis showed that a total of 815 genes were significantly changed in the stationary phase compared to the exponential phase, which consisted of 399 up-regulated and 416 down-regulated genes. The results showed that the transport and metabolism of cellobiose, xylooligosaccharides and raffinose were enhanced at the stationary phase, which expanded carbon source utilizing profile to confront with glucose consumption. Meanwhile, genes involved in cysteine-cystathionine-cycle (CCC) pathway, glutamate dehydrogenase, branched-chain amino acids (BCAAs) biosynthesis, and Clp protease were all up-regulated in the stationary phase, which may enhance the acid tolerance of B. lactis A6 during stationary phase. Acid tolerance assay indicated that the survival rate of stationary phase cells was 51.07% after treatment by pH 3.0 for 2h, which was 730-fold higher than that of 0.07% with log phase cells. In addition, peptidoglycan biosynthesis was significantly repressed, which is comparable with the decreased growth rate during the stationary phase. Remarkably, a putative gene cluster encoding Tad pili was up-regulated by 6.5 to 12.1-fold, which is consistent with the significantly increased adhesion rate to mucin from 2.38% to 4.90% during the transition from the exponential phase to the stationary phase. Conclusions This study reported growth phase-associated changes of B. lactis A6 during fermentation, including expanded carbon source utilizing profile, enhanced acid tolerance, and up-regulated Tad pili gene cluster responsible for bacterial adhesion in the stationary phase. These findings provide a novel insight into the growth phase associated characteristics in B. lactis A6 and provide valuable information for further application in the food industry. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02474-5.
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Affiliation(s)
- Hui Wang
- Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Municipality, College of Food Science and Nutritional Engineering, China Agricultural University, 17 Qing Hua East Road, Hai Dian District, Beijing, 100083, China
| | - Jieran An
- Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Municipality, College of Food Science and Nutritional Engineering, China Agricultural University, 17 Qing Hua East Road, Hai Dian District, Beijing, 100083, China
| | - Chengfei Fan
- Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Municipality, College of Food Science and Nutritional Engineering, China Agricultural University, 17 Qing Hua East Road, Hai Dian District, Beijing, 100083, China
| | - Zhengyuan Zhai
- Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Municipality, College of Food Science and Nutritional Engineering, China Agricultural University, 17 Qing Hua East Road, Hai Dian District, Beijing, 100083, China.,Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Hongxing Zhang
- Department of Food Science, Beijing University of Agriculture, 7 Bei Nong Road, Changping District, Beijing, 102206, China
| | - Yanling Hao
- Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Municipality, College of Food Science and Nutritional Engineering, China Agricultural University, 17 Qing Hua East Road, Hai Dian District, Beijing, 100083, China. .,Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
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4
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Turroni F, Milani C, Duranti S, Lugli GA, Bernasconi S, Margolles A, Di Pierro F, van Sinderen D, Ventura M. The infant gut microbiome as a microbial organ influencing host well-being. Ital J Pediatr 2020; 46:16. [PMID: 32024556 PMCID: PMC7003403 DOI: 10.1186/s13052-020-0781-0] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 01/29/2020] [Indexed: 12/16/2022] Open
Abstract
Initial establishment of the human gut microbiota is generally believed to occur immediately following birth, involving key gut commensals such as bifidobacteria that are acquired from the mother. The subsequent development of this early gut microbiota is driven and modulated by specific dietary compounds present in human milk that support selective colonization. This represents a very intriguing example of host-microbe co-evolution, where both partners are believed to benefit. In recent years, various publications have focused on dissecting microbial infant gut communities and their interaction with their human host, being a determining factor in host physiology and metabolic activities. Such studies have highlighted a reduction of microbial diversity and/or an aberrant microbiota composition, sometimes referred to as dysbiosis, which may manifest itself during the early stage of life, i.e., in infants, or later stages of life. There are growing experimental data that may explain how the early human gut microbiota affects risk factors related to adult health conditions. This concept has fueled the development of various nutritional strategies, many of which are based on probiotics and/or prebiotics, to shape the infant microbiota. In this review, we will present the current state of the art regarding the infant gut microbiota and the role of key commensal microorganisms like bifidobacteria in the establishment of the first microbial communities in the human gut.
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Affiliation(s)
- Francesca Turroni
- Laboratory of Probiogenomics, Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11a, 43124, Parma, Italy
- Microbiome Research Hub, University of Parma, Parma, Italy
| | - Christian Milani
- Laboratory of Probiogenomics, Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11a, 43124, Parma, Italy
| | - Sabrina Duranti
- Laboratory of Probiogenomics, Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11a, 43124, Parma, Italy
| | - Gabriele Andrea Lugli
- Laboratory of Probiogenomics, Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11a, 43124, Parma, Italy
| | | | - Abelardo Margolles
- Departamento de Microbiologia y Bioquimica de Productos Lacteos, IPLA - CSIC, Villaviciosa, Asturias, Spain
- Instituto de Investigación Sanitaria del Principado de Asturias-ISPA, Oviedo, Spain
| | | | - Douwe van Sinderen
- School of Microbiology & APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Marco Ventura
- Laboratory of Probiogenomics, Department of Chemistry, Life Sciences, and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11a, 43124, Parma, Italy.
- Microbiome Research Hub, University of Parma, Parma, Italy.
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5
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Bifidobacterial Transfer from Mother to Child as Examined by an Animal Model. Microorganisms 2019; 7:microorganisms7090293. [PMID: 31461893 PMCID: PMC6780879 DOI: 10.3390/microorganisms7090293] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/21/2019] [Accepted: 08/22/2019] [Indexed: 01/12/2023] Open
Abstract
Bifidobacteria commonly constitute the most abundant group of microorganisms in the healthy infant gut. Their intestinal establishment is believed to be maternally driven, and their acquisition has even been postulated to occur during pregnancy. In the current study, we evaluated bifidobacterial mother-to infant transmission events in a rat model by means of quantitative PCR (qPCR), as well as by Internally Transcribed Spacer (ITS) bifidobacterial profiling. The occurrence of strains supplied by mothers during pregnancy to their corresponding newborns was observed and identified by analysis immediately following C-section delivery. These findings provide intriguing support for the existence of an unknown route to facilitate bifidobacterial transfer during the very early stages of life.
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6
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Duranti S, Vivo V, Zini I, Milani C, Mangifesta M, Anzalone R, Mancabelli L, Viappiani A, Cantoni AM, Barocelli E, van Sinderen D, Bertoni S, Turroni F. Bifidobacterium bifidum PRL2010 alleviates intestinal ischemia/reperfusion injury. PLoS One 2018; 13:e0202670. [PMID: 30161157 PMCID: PMC6116995 DOI: 10.1371/journal.pone.0202670] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 08/07/2018] [Indexed: 02/01/2023] Open
Abstract
Mesenteric ischemia/reperfusion is a clinical emergency with high morbidity and mortality due to the transient reduction of blood supply to the bowel. In recent years, the critical contribution of gut microbiome to human health and proper gastrointestinal functions has gradually emerged. In the current study, we investigated the protective effects of five days supplementation with Bifidobacterium bifidum PRL2010 in a murine model of gut ischemia/reperfusion. Our findings indicate that animals pretreated with B. bifidum PRL2010 showed lower neutrophil recruitment in the lungs, remarkably reduced bacterial translocation and decreased transcription levels of TNFalpha and IL-10 both in liver and kidneys, at the same time increasing those of IL-12 in kidneys. Inhibiting the adhesion of pathogenic bacteria and boosting host innate immunity responses are among the possible protective mechanisms enacted by the probiotic. These results demonstrate that short-period treatment with B. bifidum PRL2010 is a potential strategy to dampen remote organ injury due to mesenteric ischemia/reperfusion.
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Affiliation(s)
- Sabrina Duranti
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
| | - Valentina Vivo
- Food and Drug Department, University of Parma, Parma, Italy
| | - Irene Zini
- Food and Drug Department, University of Parma, Parma, Italy
| | - Christian Milani
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
| | | | - Rosaria Anzalone
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
| | - Leonardo Mancabelli
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
| | - Alice Viappiani
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
| | | | - Elisabetta Barocelli
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
| | - Douwe van Sinderen
- APC Microbiome Institute and School of Microbiology, Bioscience Institute, National University of Ireland, Cork, Ireland
| | - Simona Bertoni
- Food and Drug Department, University of Parma, Parma, Italy
- * E-mail:
| | - Francesca Turroni
- Laboratory of Probiogenomics, Department of Chemical Sciences, Life Sciences, and Environmental Sustainability, University of Parma, Parma, Italy
- Microbiome Research Hub, University of Parma, Parma, Italy
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7
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The Sortase-Dependent Fimbriome of the Genus Bifidobacterium: Extracellular Structures with Potential To Modulate Microbe-Host Dialogue. Appl Environ Microbiol 2017; 83:AEM.01295-17. [PMID: 28754709 DOI: 10.1128/aem.01295-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 07/25/2017] [Indexed: 12/21/2022] Open
Abstract
Bifidobacteria are important gut commensals of mammals, including humans, of any age. However, the molecular mechanisms by which these microorganisms establish themselves in the mammalian gut and persist in this environment are largely unknown. Here, we analyzed the genetic diversity of the predicted arsenal of sortase-dependent pili of known and sequenced members of the Bifidobacterium genus and constructed a bifidobacterial sortase-dependent fimbriome database. Our analyses revealed considerable genetic variability of the sortase-dependent fimbriome among bifidobacterial (sub)species, which appears to have been due to horizontal gene transfer events and for which we were able to perform evolutionary mapping. Functional assessment by transcriptome analysis and binding assays involving different substrates demonstrates how bifidobacterial pili are pivotal in promoting various abilities for adhesion to glycans and extracellular matrix proteins, thereby supporting the ecological success of bifidobacteria in the mammalian gut.IMPORTANCE Adhesion of bifidobacterial cells to the mucosa of the large intestine is considered a hallmark for the persistence and colonization of these bacteria in the human gut. In this context, we analyzed the genetic diversity of the predicted arsenal of sortase-dependent pili of known and sequenced members of the Bifidobacterium genus, and constructed a bifidobacterial sortase-dependent fimbriome database. Our analyses revealed considerable genetic variability of the sortase-dependent fimbriome among bifidobacterial (sub)species, which appears to have been due to horizontal gene transfer events. In addition, functional assessment by transcriptome analysis and binding assays involving different substrates demonstrates how bifidobacterial pili are crucial in promoting various abilities for adhesion to glycans and extracellular matrix proteins, thereby supporting the ecological success of bifidobacteria in the mammalian gut. This study represents a complete genomic study regarding the presence of fimbriae in the genus Bifidobacterium.
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8
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Katoh T, Maeshibu T, Kikkawa KI, Gotoh A, Tomabechi Y, Nakamura M, Liao WH, Yamaguchi M, Ashida H, Yamamoto K, Katayama T. Identification and characterization of a sulfoglycosidase from Bifidobacterium bifidum implicated in mucin glycan utilization. Biosci Biotechnol Biochem 2017; 81:2018-2027. [PMID: 28814130 DOI: 10.1080/09168451.2017.1361810] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Human gut symbiont bifidobacteria possess carbohydrate-degrading enzymes that act on the O-linked glycans of intestinal mucins to utilize those carbohydrates as carbon sources. However, our knowledge about mucin type O-glycan degradation by bifidobacteria remains fragmentary, especially regarding how they decompose sulfated glycans, which are abundantly found in mucin sugar-chains. Here, we examined the abilities of several Bifidobacterium strains to degrade a sulfated glycan substrate and identified a 6-sulfo-β-d-N-acetylglucosaminidase, also termed sulfoglycosidase, encoded by bbhII from Bifidobacterium bifidum JCM 7004. A recombinant BbhII protein showed a substrate preference toward 6-sulfated and 3,4-disulfated N-acetylglucosamines over non-sulfated and 3-sulfated N-acetylglucosamines. The purified BbhII directly released 6-sulfated N-acetylglucosamine from porcine gastric mucin and the expression of bbhII was moderately induced in the presence of mucin. This de-capping activity may promote utilization of sulfated glycans of mucin by other bacteria including bifidobacteria, thereby establishing the symbiotic relationship between human and gut microbes.
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Affiliation(s)
- Toshihiko Katoh
- a Graduate School of Biostudies , Kyoto University , Kyoto , Japan.,b Faculty of Bioresources and Environmental Sciences , Ishikawa Prefectural University , Nonoichi , Ishikawa , Japan
| | - Takako Maeshibu
- a Graduate School of Biostudies , Kyoto University , Kyoto , Japan
| | - Kei-Ichi Kikkawa
- b Faculty of Bioresources and Environmental Sciences , Ishikawa Prefectural University , Nonoichi , Ishikawa , Japan
| | - Aina Gotoh
- a Graduate School of Biostudies , Kyoto University , Kyoto , Japan
| | - Yusuke Tomabechi
- b Faculty of Bioresources and Environmental Sciences , Ishikawa Prefectural University , Nonoichi , Ishikawa , Japan
| | | | - Wei-Hsiang Liao
- a Graduate School of Biostudies , Kyoto University , Kyoto , Japan
| | | | - Hisashi Ashida
- d Faculty of Biology-Oriented Science and Technology , Kindai University , Kinokawa , Japan
| | - Kenji Yamamoto
- b Faculty of Bioresources and Environmental Sciences , Ishikawa Prefectural University , Nonoichi , Ishikawa , Japan
| | - Takane Katayama
- a Graduate School of Biostudies , Kyoto University , Kyoto , Japan.,b Faculty of Bioresources and Environmental Sciences , Ishikawa Prefectural University , Nonoichi , Ishikawa , Japan
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9
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Mianzhi Y, Shah NP. Contemporary nucleic acid-based molecular techniques for detection, identification, and characterization of Bifidobacterium. Crit Rev Food Sci Nutr 2017; 57:987-1016. [PMID: 26565761 DOI: 10.1080/10408398.2015.1023761] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bifidobacteria are one of the most important bacterial groups found in the gastrointestinal tract of humans. Medical and food industry researchers have focused on bifidobacteria because of their health-promoting properties. Researchers have historically relied on classic phenotypic approaches (culture and biochemical tests) for detection and identification of bifidobacteria. Those approaches still have values for the identification and detection of some bifidobacterial species, but they are often labor-intensive and time-consuming and can be problematic in differentiating closely related species. Rapid, accurate, and reliable methods for detection, identification, and characterization of bifidobacteria in a mixed bacterial population have become a major challenge. The advent of nucleic acid-based molecular techniques has significantly advanced isolation and detection of bifidobacteria. Diverse nucleic acid-based molecular techniques have been employed, including hybridization, target amplification, and fingerprinting. Certain techniques enable the detection, characterization, and identification at genus-, species-, and strains-levels, whereas others allow typing of species or strains of bifidobacteria. In this review, an overview of methodological principle, technique complexity, and application of various nucleic acid-based molecular techniques for detection, identification, and characterization of bifidobacteria is presented. Advantages and limitations of each technique are discussed, and significant findings based on particular techniques are also highlighted.
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Affiliation(s)
- Yao Mianzhi
- a Food and Nutritional Science , School of Biological Sciences, The University of Hong Kong , Hong Kong
| | - Nagendra P Shah
- a Food and Nutritional Science , School of Biological Sciences, The University of Hong Kong , Hong Kong
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10
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Zakharova YV. FACTORS OF ADHESION OF BIFIDOBACTERIA. JOURNAL OF MICROBIOLOGY, EPIDEMIOLOGY AND IMMUNOBIOLOGY 2016. [DOI: 10.36233/0372-9311-2016-5-80-87] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Data on fimbrial and afimbrial adhesion factors of bifidobacteria are presented. Pili-like structures, their composition and conditions of formation in various species of bifidobacteria are described. Several sugar-lytic enzymes serve as afimbrial adhesins in bifidobacteria. Transaldolase and enolase are detected in bifidobacteria on cells’ surface. Transaldolase ensures binding of bifidobacteria with mucin and their auto-aggregation. Surface enolase has an affinity to plasminogen, thus bifidobacteria obtain a surface-bound protein with proteolytic activity. Molecular structures giving bifidobacteria hydrophobic properties are described - surface lipoprotein Bop A and lipoteichoic acids.
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11
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Ferrario C, Duranti S, Milani C, Mancabelli L, Lugli GA, Turroni F, Mangifesta M, Viappiani A, Ossiprandi MC, van Sinderen D, Ventura M. Exploring Amino Acid Auxotrophy in Bifidobacterium bifidum PRL2010. Front Microbiol 2015; 6:1331. [PMID: 26635786 PMCID: PMC4656816 DOI: 10.3389/fmicb.2015.01331] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 11/12/2015] [Indexed: 01/01/2023] Open
Abstract
The acquisition and assimilation strategies followed by members of the infant gut microbiota to retrieve nitrogen from the gut lumen are still largely unknown. In particular, no information on these metabolic processes is available regarding bifidobacteria, which are among the first microbial colonizers of the human intestine. Here, evaluation of amino acid auxotrophy and prototrophy of Bifidobacterium bifidum, with particular emphasis on B. bifidum strain PRL2010 (LMG S-28692), revealed a putative auxotrophy for cysteine. In addition, we hypothesized that cysteine plays a role in the oxidative stress response in B. bifidum. The use of glutathione as an alternative reduced sulfur compound did not alleviate cysteine auxotrophy of this strain, though it was shown to stimulate expression of the genes involved in cysteine biosynthesis, reminiscent of oxidative stress response. When PRL2010 was grown on a medium containing complex substrates, such as whey proteins or casein hydrolysate, we noticed a distinct growth-promoting effect of these compounds. Transcriptional analysis involving B. bifidum PRL2010 cultivated on whey proteins or casein hydrolysate revealed that the biosynthetic pathways for cysteine and methionine are modulated by the presence of casein hydrolysate. Such findings support the notion that certain complex substrates may act as potential prebiotics for bifidobacteria in their ecological niche.
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Affiliation(s)
- Chiara Ferrario
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Sabrina Duranti
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Christian Milani
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Leonardo Mancabelli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Gabriele A Lugli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Francesca Turroni
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | | | | | - Maria C Ossiprandi
- Department of Medical-Veterinary Science, University of Parma Parma, Italy
| | - Douwe van Sinderen
- APC Microbiome Institute and School of Microbiology, University College Cork, National University of Ireland Cork, Ireland
| | - Marco Ventura
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
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12
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Genome-wide identification and characterization of reference genes with different transcript abundances for Streptomyces coelicolor. Sci Rep 2015; 5:15840. [PMID: 26527303 PMCID: PMC4630627 DOI: 10.1038/srep15840] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/01/2015] [Indexed: 12/22/2022] Open
Abstract
The lack of reliable reference genes (RGs) in the genus Streptomyces hampers effort to obtain the precise data of transcript levels. To address this issue, we aimed to identify reliable RGs in the model organism Streptomyces coelicolor. A pool of potential RGs containing 1,471 genes was first identified by determining the intersection of genes with stable transcript levels from four time-series transcriptome microarray datasets of S. coelicolor M145 cultivated in different conditions. Then, following a strict rational selection scheme including homology analysis, disturbance analysis, function analysis and transcript abundance analysis, 13 candidates were selected from the 1,471 genes. Based on real-time quantitative reverse transcription PCR assays, SCO0710, SCO6185, SCO1544, SCO3183 and SCO4758 were identified as the top five genes with the most stable transcript levels among the 13 candidates. Further analyses showed these five genes also maintained stable transcript levels in different S. coelicolor strains, as well as in Streptomyces avermitilis MA-4680 and Streptomyces clavuligerus NRRL 3585, suggesting they could fulfill the requirements of accurate data normalization in streptomycetes. Moreover, the systematic strategy employed in this work could be used for reference in other microorganism to select reliable RGs.
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13
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Turroni F, Özcan E, Milani C, Mancabelli L, Viappiani A, van Sinderen D, Sela DA, Ventura M. Glycan cross-feeding activities between bifidobacteria under in vitro conditions. Front Microbiol 2015; 6:1030. [PMID: 26441950 PMCID: PMC4585166 DOI: 10.3389/fmicb.2015.01030] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 09/10/2015] [Indexed: 01/20/2023] Open
Abstract
Bifidobacteria colonize the gut of various mammals, including humans, where they may metabolize complex, diet-, and host-derived carbohydrates. The glycan-associated metabolic features encoded by bifidobacteria are believed to be strongly influenced by cross-feeding activities due to the co-existence of strains with different glycan-degrading properties. In this study, we observed an enhanced growth yield of Bifidobacterium bifidum PRL2010 when co-cultivated with Bifidobacterium breve 12L, Bifidobacterium adolescentis 22L, or Bifidobacterium thermophilum JCM1207. This enhanced growth phenomenon was confirmed by whole genome transcriptome analyses, which revealed co-cultivation-associated transcriptional induction of PRL2010 genes involved in carbohydrate metabolism, such as those encoding for carbohydrate transporters and associated energy production, and genes required for translation, ribosomal structure, and biogenesis, thus supporting the idea that co-cultivation of certain bifidobacterial strains with B. bifidum PRL2010 causes enhanced metabolic activity, and consequently increased lactate and/or acetate production. Overall, these data suggest that PRL2010 cells benefit from the presence of other bifidobacterial strains.
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Affiliation(s)
- Francesca Turroni
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma Italy
| | - Ezgi Özcan
- Department of Food Science, University of Massachusetts Amherst, Amherst, MA USA
| | - Christian Milani
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma Italy
| | - Leonardo Mancabelli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma Italy
| | | | - Douwe van Sinderen
- Alimentary Pharmabiotic Centre and Department of Microbiology, Bioscience Institute, National University of Ireland, Cork Ireland
| | - David A Sela
- Department of Food Science, University of Massachusetts Amherst, Amherst, MA USA ; Center for Microbiome Research, University of Massachusetts Medical School, Worcester, MA USA
| | - Marco Ventura
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma Italy
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Mutual Cross-Feeding Interactions between Bifidobacterium longum subsp. longum NCC2705 and Eubacterium rectale ATCC 33656 Explain the Bifidogenic and Butyrogenic Effects of Arabinoxylan Oligosaccharides. Appl Environ Microbiol 2015; 81:7767-81. [PMID: 26319874 DOI: 10.1128/aem.02089-15] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/25/2015] [Indexed: 02/07/2023] Open
Abstract
Arabinoxylan oligosaccharides (AXOS) are a promising class of prebiotics that have the potential to stimulate the growth of bifidobacteria and the production of butyrate in the human colon, known as the bifidogenic and butyrogenic effects, respectively. Although these dual effects of AXOS are considered beneficial for human health, their underlying mechanisms are still far from being understood. Therefore, this study investigated the metabolic interactions between Bifidobacterium longum subsp. longum NCC2705 (B. longum NCC2705), an acetate producer and arabinose substituent degrader of AXOS, and Eubacterium rectale ATCC 33656, an acetate-converting butyrate producer. Both strains belong to prevalent species of the human colon microbiota. The strains were grown on AXOS during mono- and coculture fermentations, and their growth, AXOS consumption, metabolite production, and expression of key genes were monitored. The results showed that the growth of both strains and gene expression in both strains were affected by cocultivation and that these effects could be linked to changes in carbohydrate consumption and concomitant metabolite production. The consumption of the arabinose substituents of AXOS by B. longum NCC2705 with the concomitant production of acetate allowed E. rectale ATCC 33656 to produce butyrate (by means of a butyryl coenzyme A [CoA]:acetate CoA-transferase), explaining the butyrogenic effect of AXOS. Eubacterium rectale ATCC 33656 released xylose from the AXOS substrate, which favored the B. longum NCC2705 production of acetate, explaining the bifidogenic effect of AXOS. Hence, those interactions represent mutual cross-feeding mechanisms that favor the coexistence of bifidobacterial strains and butyrate producers in the same ecological niche. In conclusion, this study provides new insights into the bifidogenic and butyrogenic effects of AXOS.
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Colagiorgi A, Turroni F, Mancabelli L, Serafini F, Secchi A, van Sinderen D, Ventura M. Insights into teichoic acid biosynthesis byBifidobacterium bifidumPRL2010. FEMS Microbiol Lett 2015; 362:fnv141. [DOI: 10.1093/femsle/fnv141] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2015] [Indexed: 12/23/2022] Open
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Bacterial reference genes for gene expression studies by RT-qPCR: survey and analysis. Antonie van Leeuwenhoek 2015; 108:685-93. [PMID: 26149127 DOI: 10.1007/s10482-015-0524-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 06/29/2015] [Indexed: 10/23/2022]
Abstract
The appropriate choice of reference genes is essential for accurate normalization of gene expression data obtained by the method of reverse transcription quantitative real-time PCR (RT-qPCR). In 2009, a guideline called the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) highlighted the importance of the selection and validation of more than one suitable reference gene for obtaining reliable RT-qPCR results. Herein, we searched the recent literature in order to identify the bacterial reference genes that have been most commonly validated in gene expression studies by RT-qPCR (in the first 5 years following publication of the MIQE guidelines). Through a combination of different search parameters with the text mining tool MedlineRanker, we identified 145 unique bacterial genes that were recently tested as candidate reference genes. Of these, 45 genes were experimentally validated and, in most of the cases, their expression stabilities were verified using the software tools geNorm and NormFinder. It is noteworthy that only 10 of these reference genes had been validated in two or more of the studies evaluated. An enrichment analysis using Gene Ontology classifications demonstrated that genes belonging to the functional categories of DNA Replication (GO: 0006260) and Transcription (GO: 0006351) rendered a proportionally higher number of validated reference genes. Three genes in the former functional class were also among the top five most stable genes identified through an analysis of gene expression data obtained from the Pathosystems Resource Integration Center. These results may provide a guideline for the initial selection of candidate reference genes for RT-qPCR studies in several different bacterial species.
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Duranti S, Milani C, Lugli GA, Turroni F, Mancabelli L, Sanchez B, Ferrario C, Viappiani A, Mangifesta M, Mancino W, Gueimonde M, Margolles A, van Sinderen D, Ventura M. Insights from genomes of representatives of the human gut commensal Bifidobacterium bifidum. Environ Microbiol 2015; 17:2515-31. [PMID: 25523018 DOI: 10.1111/1462-2920.12743] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 11/25/2014] [Accepted: 12/03/2014] [Indexed: 11/27/2022]
Abstract
Bifidobacteria are bacterial gut commensals of mammals, birds and social insects that are perceived to influence the metabolism/physiology of their host. In this context, members of the Bifidobacterium bifidum species are believed to significantly contribute to the overall microbiota of the human gut at infant stage. However, the molecular reasons for their adaptation to this environment are poorly understood. In this study, we analysed the pan-genome of B. bifidum species by decoding genomes of 15 B. bifidum strains, which highlighted the existence of a conserved gene uniquely present in this bifidobacterial taxon, underscoring a nutrient acquisition strategy that targets host-derived glycans, such as those present in mucin. Growth experiments and corresponding transcriptomic analyses confirmed the in silico data and supported these intriguing and unique host glycan-specific saccharolytic features. The ubiquity of the genetic features of B. bifidum for the breakdown of host glycans was confirmed by interrogating metagenomic datasets, thereby supporting the notion that metabolic access to host-derived glycans is a potent evolutionary force that has shaped B. bifidum genomes and consequently the ecology of the infant intestinal microbiota.
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Affiliation(s)
- Sabrina Duranti
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Christian Milani
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Gabriele Andrea Lugli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Francesca Turroni
- Alimentary Pharmabiotic Centre and Department of Microbiology, Bioscience Institute, National University of Ireland, Cork, Ireland
| | - Leonardo Mancabelli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Borja Sanchez
- Departamento de Microbiologia y Bioquimica de Productos Lacteos, Consejo Superior de Investigaciones Científicas, CSIC, Villaviciosa, Asturias, Spain
| | - Chiara Ferrario
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Alice Viappiani
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Marta Mangifesta
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Walter Mancino
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
| | - Miguel Gueimonde
- Departamento de Microbiologia y Bioquimica de Productos Lacteos, Consejo Superior de Investigaciones Científicas, CSIC, Villaviciosa, Asturias, Spain
| | - Abelardo Margolles
- Departamento de Microbiologia y Bioquimica de Productos Lacteos, Consejo Superior de Investigaciones Científicas, CSIC, Villaviciosa, Asturias, Spain
| | - Douwe van Sinderen
- Alimentary Pharmabiotic Centre and Department of Microbiology, Bioscience Institute, National University of Ireland, Cork, Ireland
| | - Marco Ventura
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma, Parma, Italy
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Genomic characterization and transcriptional studies of the starch-utilizing strain Bifidobacterium adolescentis 22L. Appl Environ Microbiol 2014; 80:6080-90. [PMID: 25063659 DOI: 10.1128/aem.01993-14] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Bifidobacteria are members of the gut microbiota, but the genetic basis for their adaptation to the human gut is poorly understood. The analysis of the 2,203,222-bp genome of Bifidobacterium adolescentis 22L revealed a nutrient acquisition strategy that targets diet/plant-derived glycans, in particular starch and starch-like carbohydrates. Starch-like carbohydrates were shown to support the growth of B. adolescentis 22L. Transcriptome profiling of 22L cultures grown under in vitro conditions or during colonization of the murine gut by RNA sequencing and quantitative real-time PCR assays revealed the expression of a set of chromosomal loci responsible for starch metabolism as well as for pilus production. Such extracellular structures include so-called sortase-dependent and type IVb pili, which may be involved in gut colonization of 22L through adhesion to extracellular matrix proteins.
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Turroni F, Serafini F, Mangifesta M, Arioli S, Mora D, van Sinderen D, Ventura M. Expression of sortase-dependent pili ofBifidobacterium bifidumPRL2010 in response to environmental gut conditions. FEMS Microbiol Lett 2014; 357:23-33. [DOI: 10.1111/1574-6968.12509] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 06/12/2014] [Accepted: 06/13/2014] [Indexed: 11/27/2022] Open
Affiliation(s)
- Francesca Turroni
- Alimentary Pharmabiotic Centre and Department of Microbiology; Bioscience Institute; National University of Ireland; Cork Ireland
| | - Fausta Serafini
- Department of Life Sciences; Laboratory of Probiogenomics; University of Parma; Parma Italy
| | | | - Stefania Arioli
- Department of Food Environmental and Nutritional Sciences; University of Milan; Milan Italy
| | - Diego Mora
- Department of Food Environmental and Nutritional Sciences; University of Milan; Milan Italy
| | - Douwe van Sinderen
- Alimentary Pharmabiotic Centre and Department of Microbiology; Bioscience Institute; National University of Ireland; Cork Ireland
| | - Marco Ventura
- Department of Life Sciences; Laboratory of Probiogenomics; University of Parma; Parma Italy
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Kefir fermented milk and kefiran promote growth of Bifidobacterium bifidum PRL2010 and modulate its gene expression. Int J Food Microbiol 2014; 178:50-9. [DOI: 10.1016/j.ijfoodmicro.2014.02.024] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/21/2014] [Accepted: 02/27/2014] [Indexed: 12/28/2022]
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Bifidobacterium bifidum PRL2010 modulates the host innate immune response. Appl Environ Microbiol 2013; 80:730-40. [PMID: 24242237 DOI: 10.1128/aem.03313-13] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Here, we describe data obtained from transcriptome profiling of human cell lines and intestinal cells of a murine model upon exposure and colonization, respectively, with Bifidobacterium bifidum PRL2010. Significant changes were detected in the transcription of genes that are known to be involved in innate immunity. Furthermore, results from enzyme-linked immunosorbent assays (ELISAs) showed that exposure to B. bifidum PRL2010 causes enhanced production of interleukin 6 (IL-6) and IL-8 cytokines, presumably through NF-κB activation. The obtained global transcription profiles strongly suggest that Bifidobacterium bifidum PRL2010 modulates the innate immune response of the host.
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23
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Serafini F, Strati F, Ruas-Madiedo P, Turroni F, Foroni E, Duranti S, Milano F, Perotti A, Viappiani A, Guglielmetti S, Buschini A, Margolles A, van Sinderen D, Ventura M. Evaluation of adhesion properties and antibacterial activities of the infant gut commensal Bifidobacterium bifidum PRL2010. Anaerobe 2013; 21:9-17. [PMID: 23523946 DOI: 10.1016/j.anaerobe.2013.03.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 02/28/2013] [Accepted: 03/04/2013] [Indexed: 01/10/2023]
Abstract
Bifidobacteria are extensively exploited by the food industry as health-promoting microorganisms. However, very little is known about the molecular mechanisms responsible for these beneficial activities, or the molecular players that sustain their ability to colonize and persist within the human gut. Here, we have investigated the enteric adaptation features of the gut commensal Bifidobacterium bifidum PRL2010, originally isolated from infant feces. This strain was able to survive under gastrointestinal challenges, while it was shown to adhere to human epithelial intestinal cell monolayers (Caco 2 and HT-29), thereby inhibiting adhesion of pathogenic bacteria such as Escherichia coli and Cronobacter sakazakii.
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Affiliation(s)
- Fausta Serafini
- Department of Genetics, Biology of Microorganisms, Anthropology and Evolution, University of Parma, Parma, Italy
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A two-component regulatory system controls autoregulated serpin expression in Bifidobacterium breve UCC2003. Appl Environ Microbiol 2012; 78:7032-41. [PMID: 22843530 DOI: 10.1128/aem.01776-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
This work reports on the identification and molecular characterization of a two-component regulatory system (2CRS), encoded by serRK, which is believed to control the expression of the ser(2003) locus in Bifidobacterium breve UCC2003. The ser(2003) locus consists of two genes, Bbr_1319 (sagA) and Bbr_1320 (serU), which are predicted to encode a hypothetical membrane-associated protein and a serpin-like protein, respectively. The response regulator SerR was shown to bind to the promoter region of ser(2003), and the probable recognition sequence of SerR was determined by a combinatorial approach of in vitro site-directed mutagenesis coupled to transcriptional fusion and electrophoretic mobility shift assays (EMSAs). The importance of the serRK 2CRS in the response of B. breve to protease-mediated induction was confirmed by generating a B. breve serR insertion mutant, which was shown to exhibit altered ser(2003) transcriptional induction patterns compared to the parent strain, UCC2003. Interestingly, the analysis of a B. breve serU mutant revealed that the SerRK signaling pathway appears to include a SerU-dependent autoregulatory loop.
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Analysis of predicted carbohydrate transport systems encoded by Bifidobacterium bifidum PRL2010. Appl Environ Microbiol 2012; 78:5002-12. [PMID: 22562993 DOI: 10.1128/aem.00629-12] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Bifidobacterium bifidum PRL2010 genome encodes a relatively small set of predicted carbohydrate transporters. Growth experiments and transcriptome analyses of B. bifidum PRL2010 revealed that carbohydrate utilization in this microorganism appears to be restricted to a relatively low number of carbohydrates.
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