scholarly journals A Novel Major Pilin Subunit Protein FimM Is Involved in Adhesion of Bifidobacterium longum BBMN68 to Intestinal Epithelial Cells

2020 ◽  
Vol 11 ◽  
Author(s):  
Yao Xiong ◽  
Zhengyuan Zhai ◽  
Yuanqiu Lei ◽  
Bingbing Xiao ◽  
Yanling Hao
Keyword(s):  
Sequence Similarity ◽  
Bifidobacterium Longum ◽  
Bifidobacterium Bifidum ◽  
Extracellular Proteins ◽  
Surface Proteins ◽  
Host Cells ◽  
Immunogold Electron Microscopy ◽  
Specific Class ◽  
Subunit Protein ◽  
Pilin Subunit

Adhesion to the gastrointestinal tract is considered to be important for bifidobacteria to colonize the human gut and exert their probiotic effects. Some cell surface proteins of bifidobacteria, known as adhesins, play critical roles in the binding to host cells or the extracellular matrix (ECM). To elucidate the mechanisms associated with the adhesion of Bifidobacterium longum BBMN68, a centenarian originated potential probiotic, PSORTdb was employed to identify putative extracellular localized proteins in the B. longum BBMN68. Of the 560 predicted extracellular proteins, 21 were further identified as putative adhesion proteins using the conserved domain database of NCBI, and four were successfully overexpressed in the heterologous host, Lactococcus lactis NZ9000. Notably, a recombinant strain expressing FimM showed a significantly increased adhesive affinity for both HT-29 and mucus-secreting LS174T goblet cells (2.2- and 5.4-fold higher than that of the control strain, respectively). Amino acid sequence alignment showed that FimM is a major pilin subunit protein containing a Cna-B type domain and a C-terminal LPKTG sequence. However, in silico analysis of the fimM-coding cluster revealed that BBMN68_RS10200, encoding a pilus-specific class C sortase, was a pseudogene, indicating that FimM may function as a surface adhesin that cannot polymerize into a pili-like structure. Immunogold electron microscopy results further confirmed that FimM localized to the surface of L. lactis NZfimM and B. longum BBMN68 but did not assemble into pilus filaments. Moreover, the adhesive affinity of L. lactis NZfimM to fibronectin, fibrinogen, and mucin were 3.8-, 2.1-, and 3.1-fold higher than that of the control. The affinity of FimM for its attachment receptors was further verified through an inhibition assay using anti-FimM antibodies. In addition, homologs of FimM were found in Bifidobacterium bifidum 85B, Bifidobacterium gallinarum CACC 514, and 23 other B. longum strains by sequence similarity analysis using BLASTP. Our results suggested that FimM is a novel surface adhesin that is mainly present in B. longum strains.

scholarly journals Role of Extracellular Transaldolase from Bifidobacterium bifidum in Mucin Adhesion and Aggregation

2012 ◽  
Vol 78 (11) ◽  
pp. 3992-3998 ◽  
Author(s):  
Irene González-Rodríguez ◽  
Borja Sánchez ◽  
Lorena Ruiz ◽  
Francesca Turroni ◽  
Marco Ventura ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Bifidobacterium Bifidum ◽  
Surface Proteins ◽  
Proteinase K ◽  
Intestinal Cell ◽  
Immunogold Electron Microscopy ◽  
Content Type ◽  
Colonization Factor ◽  
Intestinal Cell Line

ABSTRACTThe ability of bifidobacteria to establish in the intestine of mammals is among the main factors considered to be important for achieving probiotic effects. The role of surface molecules fromBifidobacterium bifidumtaxon in mucin adhesion capability and the aggregation phenotype of this bacterial species was analyzed. Adhesion to the human intestinal cell line HT29 was determined for a collection of 12B. bifidumstrains. In four of them—B. bifidumLMG13195, DSM20456, DSM20239, and A8—the involvement of surface-exposed macromolecules in the aggregation phenomenon was determined. The aggregation ofB. bifidumA8 and DSM20456 was abolished after treatment with proteinase K, this effect being more pronounced for the strain A8. Furthermore, a mucin binding assay ofB. bifidumA8 surface proteins showed a high adhesive capability for its transaldolase (Tal). The localization of this enzyme on the surface ofB. bifidumA8 was unequivocally demonstrated by immunogold electron microscopy experiments. The gene encoding Tal fromB. bifidumA8 was expressed inLactococcus lactis, and the protein was purified to homogeneity. The pure protein was able to restore the autoaggregation phenotype of proteinase K-treatedB. bifidumA8 cells. A recombinantL. lactisstrain, engineered to secrete Tal, displayed a mucin- binding level more than three times higher than the strain not producing the transaldolase. These findings suggest that Tal, when exposed on the cell surface ofB. bifidum, could act as an important colonization factor favoring its establishment in the gut.

Galacto- and Fructo-oligosaccharides Utilized for Growth by Cocultures of Bifidobacterial Species Characteristic of the Infant Gut

2020 ◽  
Author(s):  
Ian Sims ◽  
GW Tannock
Keyword(s):  
Breast Milk ◽  
Bacterial Species ◽  
Bifidobacterium Longum ◽  
Well Being ◽  
Bifidobacterium Bifidum ◽  
Child Rearing ◽  
Potential Growth ◽  
Human Infants ◽  
Infant Diet ◽  
Growth Substrates

Copyright © 2020 American Society for Microbiology. Bifidobacterial species are common inhabitants of the gut of human infants during the period when milk is a major component of the diet. Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium longum subspecies longum, and B. longum subspecies infantis have been detected frequently in infant feces, but B. longum subsp. infantis may be disadvantaged numerically in the gut of infants in westernized countries. This may be due to the different durations of breast milk feeding in different countries. Supplementation of the infant diet or replacement of breast milk using formula feeds is common in Western countries. Formula milks often contain galacto- and/or fructo-oligosaccharides (GOS and FOS, respectively) as additives to augment the concentration of oligosaccharides in ruminant milks, but the ability of B. longum subsp. infantis to utilize these potential growth substrates when they are in competition with other bifidobacterial species is unknown. We compared the growth and oligosaccharide utilization of GOS and FOS by bifidobacterial species in pure culture and coculture. Short-chain GOS and FOS (degrees of polymerization [DP] 2 and 3) were favored growth substrates for strains of B. bifidum and B. longum subsp. longum, whereas both B. breve and B. longum subsp. infantis had the ability to utilize both short- and longer-chain GOS and FOS (DP 2 to 6). B. breve was nevertheless numerically dominant over B. longum subsp. infantis in cocultures. This was probably related to the slower use of GOS of DP 3 by B. longum subsp. infantis, indicating that the kinetics of substrate utilization is an important ecological factor in the assemblage of gut communities.IMPORTANCE The kinds of bacteria that form the collection of microbes (the microbiota) in the gut of human infants may influence health and well-being. Knowledge of how the composition of the infant diet influences the assemblage of the bacterial collection is therefore important because dietary interventions may offer opportunities to alter the microbiota with the aim of improving health. Bifidobacterium longum subspecies infantis is a well-known bacterial species, but under modern child-rearing conditions it may be disadvantaged in the gut. Modern formula milks often contain particular oligosaccharide additives that are generally considered to support bifidobacterial growth. However, studies of the ability of various bifidobacterial species to grow together in the presence of these oligosaccharides have not been conducted. These kinds of studies are essential for developing concepts of microbial ecology related to the influence of human nutrition on the development of the gut microbiota.

scholarly journals Lipoproteins Are Responsible for the Pro-Inflammatory Property of Staphylococcus aureus Extracellular Vesicles

2021 ◽  
Vol 22 (13) ◽  
pp. 7099
Author(s):  
Pradeep Kumar Kopparapu ◽  
Meghshree Deshmukh ◽  
Zhicheng Hu ◽  
Majd Mohammad ◽  
Marco Maugeri ◽  
...  
Keyword(s):  
Extracellular Vesicles ◽  
Inflammatory Responses ◽  
Surface Proteins ◽  
Host Cells ◽  
Immune Stimulation ◽  
Domains Of Life ◽  
Major Surface ◽  
Staphylococcal Aureus

Staphylococcal aureus (S. aureus), a Gram-positive bacteria, is known to cause various infections. Extracellular vesicles (EVs) are a heterogeneous array of membranous structures secreted by cells from all three domains of life, i.e., eukaryotes, bacteria, and archaea. Bacterial EVs are implied to be involved in both bacteria–bacteria and bacteria–host interactions during infections. It is still unclear how S. aureus EVs interact with host cells and induce inflammatory responses. In this study, EVs were isolated from S. aureus and mutant strains deficient in either prelipoprotein lipidation (Δlgt) or major surface proteins (ΔsrtAB). Their immunostimulatory capacities were assessed both in vitro and in vivo. We found that S. aureus EVs induced pro-inflammatory responses both in vitro and in vivo. However, this activity was dependent on lipidated lipoproteins (Lpp), since EVs isolated from the Δlgt showed no stimulation. On the other hand, EVs isolated from the ΔsrtAB mutant showed full immune stimulation, indicating the cell wall anchoring of surface proteins did not play a role in immune stimulation. The immune stimulation of S. aureus EVs was mediated mainly by monocytes/macrophages and was TLR2 dependent. In this study, we demonstrated that not only free Lpp but also EV-imbedded Lpp had high pro-inflammatory activity.

scholarly journals Targeting Viral Surface Proteins through Structure-Based Design

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1320
Author(s):  
Yogesh B Narkhede ◽  
Karen J Gonzalez ◽  
Eva-Maria Strauch
Keyword(s):  
Public Health ◽  
Viral Infections ◽  
Respiratory Viruses ◽  
Surface Proteins ◽  
Host Cells ◽  
Viral Fusion ◽  
Health It ◽  
Viral Particles ◽  
Pathogenic Viruses ◽  
Viral Surface

The emergence of novel viral infections of zoonotic origin and mutations of existing human pathogenic viruses represent a serious concern for public health. It warrants the establishment of better interventions and protective therapies to combat the virus and prevent its spread. Surface glycoproteins catalyzing the fusion of viral particles and host cells have proven to be an excellent target for antivirals as well as vaccines. This review focuses on recent advances for computational structure-based design of antivirals and vaccines targeting viral fusion machinery to control seasonal and emerging respiratory viruses.

scholarly journals Extracellular Proteome Analysis Shows the Abundance of Histidine Kinase Sensor Protein, DNA Helicase, Putative Lipoprotein Containing Peptidase M75 Domain and Peptidase C39 Domain Protein in Leptospira interrogans Grown in EMJH Medium

Pathogens ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 852
Author(s):  
Abhijit Sarma ◽  
Dhandapani Gunasekaran ◽  
Devasahayam Arokia Balaya Rex ◽  
Thoduvayil Sikha ◽  
Homen Phukan ◽  
...  
Keyword(s):  
Culture Medium ◽  
Proteome Analysis ◽  
Dna Helicase ◽  
Extracellular Proteins ◽  
Surface Proteins ◽  
Secretory Proteins ◽  
Extracellular Proteome ◽  
Cell Pellet ◽  
The Difference ◽  
Leptospira Species

Leptospirosis is a re-emerging form of zoonosis that is caused by the spirochete pathogen Leptospira. Extracellular proteins play critical roles in the pathogenicity and survival of this pathogen in the host and environment. Extraction and analysis of extracellular proteins is a difficult task due to the abundance of enrichments like serum and bovine serum albumin in the culture medium, as is distinguishing them from the cellular proteins that may reach the analyte during extraction. In this study, extracellular proteins were separated as secretory proteins from the culture supernatant and surface proteins were separated during the washing of the cell pellet. The proteins identified were sorted based on the proportion of the cellular fractions and the extracellular fractions. The results showed the identification of 56 extracellular proteins, out of which 19 were exclusively extracellular. For those proteins, the difference in quantity with respect to their presence within the cell was found to be up to 1770-fold. Further, bioinformatics analysis elucidated characteristics and functions of the identified proteins. Orthologs of extracellular proteins in various Leptospira species were found to be closely related among different pathogenic forms. In addition to the identification of extracellular proteins, this study put forward a method for the extraction and identification of extracellular proteins.

scholarly journals Heterologously Expressed Staphylococcus aureusFibronectin-Binding Proteins Are Sufficient for Invasion of Host Cells

2000 ◽  
Vol 68 (12) ◽  
pp. 6871-6878 ◽  
Author(s):  
Bhanu Sinha ◽  
Patrice Francois ◽  
Yok-Ai Que ◽  
Muzaffar Hussain ◽  
Christine Heilmann ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Binding Proteins ◽  
Surface Protein ◽  
Latex Agglutination ◽  
Surface Proteins ◽  
Host Cells ◽  
Gram Positive ◽  
Fibronectin Receptor ◽  
293 Cells ◽  
Accessible Surface

ABSTRACT Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureusfibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin α5β1 (B. Sinha et al., Cell. Microbiol. 1:101–117, 1999). However, it is unknown whether this mechanism is sufficient for S. aureus invasion. To address this question, various S. aureus adhesins (FnBPA, FnBPB, and clumping factor [ClfA]) were expressed in Staphylococcus carnosus and Lactococcus lactis subsp.cremoris. Both noninvasive gram-positive microorganisms are genetically distinct from S. aureus, lack any knownS. aureus surface protein, and do not bind fibronectin. Transformants of S. carnosus and L. lactisharboring plasmids coding for various S. aureus surface proteins (FnBPA, FnBPB, and ClfA) functionally expressed adhesins (as determined by bacterial clumping in plasma, specific latex agglutination, Western ligand blotting, and binding to immobilized and soluble fibronectin). FnBPA or FnBPB but not of ClfA conferred invasiveness to S. carnosus and L. lactis. Invasion of 293 cells by transformants was comparable to that of strongly invasive S. aureus strain Cowan 1. Binding of soluble and immobilized fibronectin paralleled invasiveness, demonstrating that the amount of accessible surface FnBPs is rate limiting. Thus, S. aureus FnBPs confer invasiveness to noninvasive, apathogenic gram-positive cocci. Furthermore, FnBP-coated polystyrene beads were internalized by 293 cells, demonstrating that FnBPs are sufficient for invasion of host cells without the need for (S. aureus-specific) coreceptors.

scholarly journals Bifidobacterium bifidum R0071 results in a greater proportion of healthy days and a lower percentage of academically stressed students reporting a day of cold/flu: a randomised, double-blind, placebo-controlled study

2015 ◽  
Vol 113 (3) ◽  
pp. 426-434 ◽  
Author(s):  
Bobbi Langkamp-Henken ◽  
Cassie C. Rowe ◽  
Amanda L. Ford ◽  
Mary C. Christman ◽  
Carmelo Nieves ◽  
...  
Keyword(s):  
Acute Stress ◽  
Bifidobacterium Longum ◽  
Daily Intake ◽  
Bifidobacterium Bifidum ◽  
Lactobacillus Helveticus ◽  
Lower Percentage ◽  
Controlled Study ◽  
Double Blind ◽  
Double Blind Placebo ◽  
Symptom Intensity

Acute psychological stress is positively associated with a cold/flu. The present randomised, double-blind, placebo-controlled study examined the effect of three potentially probiotic bacteria on the proportion of healthy days over a 6-week period in academically stressed undergraduate students (n 581) who received Lactobacillus helveticus R0052, Bifidobacterium longum ssp. infantis R0033, Bifidobacterium bifidum R0071 or placebo. On each day, participants recorded the intensity (scale: 0 = not experiencing to 3 = very intense) for nine cold/flu symptoms, and a sum of symptom intensity >6 was designated as a day of cold/flu. B. bifidum resulted in a greater proportion of healthy days than placebo (P≤ 0·05). The percentage of participants reporting ≥ 1 d of cold/flu during the 6-week intervention period was significantly lower with B. bifidum than with placebo (P< 0·05). There were no effects of B. infantis or L. helveticus compared with placebo on either outcome. A predictive model accounted for influential characteristics and their interactions on daily reporting of cold/flu episodes. The proportion of participants reporting a cold on any given day was lower at weeks 2 and 3 with B. bifidum and B. infantis than with placebo for the average level of stress and the most commonly reported number of hours of sleep. Daily intake of bifidobacteria provides benefit related to cold/flu outcomes during acute stress.

scholarly journals BspA and Pmp proteins ofTrichomonas vaginalismediate adherence to host cells

2018 ◽  
Author(s):  
Maria R. Handrich ◽  
Sriram G. Garg ◽  
Ewen W. Sommerville ◽  
Robert P. Hirt ◽  
Sven B. Gould
Keyword(s):  
Trichomonas Vaginalis ◽  
Functional Characterization ◽  
Surface Proteins ◽  
Host Cells ◽  
Protein Families ◽  
Sexually Transmitted ◽  
Trace Back ◽  
Oral Pathogens ◽  
Adhesion Performance

AbstractTrichomonas vaginalisis one of the most widespread, sexually transmitted pathogens. The infection involves a morphological switch from a free-swimming pyriform trophozoite to an amoeboid cell upon adhesion to host epithelial cells. While details on how the switch is induced and to what proteins of the host surface the parasite adheres remain poorly characterized, several surface proteins of the parasite itself have been identified as potential candidates. Among those are two expanded protein families that harbor domains that share similarity to functionally investigated surface proteins of prokaryotic oral pathogens; these are the BspA proteins of Bacteroidales and Spirochaetales, and the Pmp proteins of Chlamydiales. We sequenced the transcriptomes of five Trichomonads and screened for the presence of BspA and Pmp domain-containing proteins and tested the ability of individualT. vaginaliscandidates to mediate adhesion. Here we demonstrate that (i) BspA and Pmp domain-containing proteins are specifically expanded inT. vaginalisin comparison to other Trichomonads, and that (ii) individual proteins of both families have the ability to increase adhesion performance in a non-virulentT. vaginalisstrain andTetratrichomonas gallinarum, a parasite usually known to infect birds but not humans. Our results initiate the functional characterization of these two broadly distributed protein families, whose origin we trace back to the origin of Trichomonads themselves.

scholarly journals A genomic and proteomic analysis of surface proteins in bovine-adapted lineages of Staphylococcus aureus

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Shauna D. Drumm ◽  
Rebecca Owens ◽  
Jennifer Mitchell ◽  
Orla M. Keane
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Surface Proteins ◽  
Host Cells ◽  
Mass Spectrometry Analysis ◽  
In Vitro Assays ◽  
Immune Recognition ◽  
Independent Manner ◽  
Genes Encoding

In Ireland, Staphylococcus aureus is the most common cause of intramammary infection (IMI) in cattle with the bovine-adapted lineages CC151 and CC97 most commonly found. Surface proteins play a major role in establishing and maintaining the infection. A previous study revealed that a strain from the CC151 lineage showed significant decay in genes encoding predicted surface proteins. Twenty-three S. aureus strains, twelve belonging to CC151 and eleven belonging to CC97, isolated from clinical IMI, were sequenced and genes encoding cell wall anchored (CWA) proteins predicted. Analysis showed that a minority of genes encoding putative CWA proteins were intact in the CC151 strains compared to CC97. Of the 26 known CWA proteins in S. aureus, the CC151 strains only encoded 10 intact genes while CC97 encoded on average 18 genes. Also within the CC97 lineage, the repertoire of genes varied depending on individual strains, with strains encoding between 17-20 intact genes. Although CC151 is reported to internalize within bovine host cells, it does so in a fibronectin-binding protein (FnBPA and FnBPB) independent manner. In-vitro assays were performed and results showed that strains from CC151, and surprisingly also CC97, weakly bound bovine fibronectin and that the FnBPs were poorly expressed in both these lineages. Mass spectrometry analysis of cell wall extracts revealed that SdrE and AdsA were the most highly expressed CWA proteins in both lineages. These results demonstrate significant differences between CC151 and CC97 in their repertoire of genes encoding CWA proteins, which may impact immune recognition of these strains and their interactions with host cells.

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