scholarly journals Identification and Characterization of a Novel Adhesin Unique to Oral Fusobacteria

2005 ◽  
Vol 187 (15) ◽  
pp. 5330-5340 ◽  
Author(s):  
Yiping W. Han ◽  
Akihiko Ikegami ◽  
Chythanya Rajanna ◽  
Hameem I. Kawsar ◽  
Yun Zhou ◽  
...  
Keyword(s):  
Chinese Hamster ◽  
Fusobacterium Nucleatum ◽  
The Body ◽  
Surface Proteins ◽  
Wild Type ◽  
Kb Cells ◽  
Ovarian Cells ◽  
Molecular Masses ◽  
Identification And Characterization

ABSTRACT Fusobacterium nucleatum is a gram-negative anaerobe that is prevalent in periodontal disease and infections of different parts of the body. The organism has remarkable adherence properties, binding to partners ranging from eukaryotic and prokaryotic cells to extracellular macromolecules. Understanding its adherence is important for understanding the pathogenesis of F. nucleatum. In this study, a novel adhesin, FadA (Fusobacterium adhesin A), was demonstrated to bind to the surface proteins of the oral mucosal KB cells. FadA is composed of 129 amino acid (aa) residues, including an 18-aa signal peptide, with calculated molecular masses of 13.6 kDa for the intact form and 12.6 kDa for the secreted form. It is highly conserved among F. nucleatum, Fusobacterium periodonticum, and Fusobacterium simiae, the three most closely related oral species, but is absent in the nonoral species, including Fusobacterium gonidiaformans, Fusobacterium mortiferum, Fusobacterium naviforme, Fusobacterium russii, and Fusobacterium ulcerans. In addition to FadA, F. nucleatum ATCC 25586 and ATCC 49256 also encode two paralogues, FN1529 and FNV2159, each sharing 31% identity with FadA. A double-crossover fadA deletion mutant, F. nucleatum 12230-US1, was constructed by utilizing a novel sonoporation procedure. The mutant had a slightly slower growth rate, yet its binding to KB and Chinese hamster ovarian cells was reduced by 70 to 80% compared to that of the wild type, indicating that FadA plays an important role in fusobacterial colonization in the host. Furthermore, due to its uniqueness to oral Fusobacterium species, fadA may be used as a marker to detect orally related fusobacteria. F. nucleatum isolated from other parts of the body may originate from the oral cavity.

scholarly journals Identification and characterization of phytoconstituents of ethanolic root extract of Clitoria ternatea L. utilizing HR-LCMS analysis

2021 ◽  
Vol 8 (3) ◽  
Author(s):  
K N Jiji ◽  
P Muralidharan
Keyword(s):  
Nervous System ◽  
Medicinal Plants ◽  
The Body ◽  
Major Constituent ◽  
Root Extract ◽  
Active Metabolites ◽  
Clitoria Ternatea ◽  
Intellectual Capacity ◽  
Identification And Characterization

Medicinal plants act as a vital source in improving health and overcoming the side effects of modern-day medicine. Many evidence-based reports are present in the literature about the benefits of medicinal plants. Clitoria ternatea L. belongs to the family Fabaceae and is known to be one of the important Ayurvedic medicinal plant whose uses are specified mainly for the modification of nervous system activities. ‘Medhyarasayana’ is one of the Ayurvedic formulations which is used to promote the intellectual capacity, revive the body and nervous tissue, Clitoria ternatea serves as a major constituent of ‘Medhyarasayana.’ Identification and characterization of active metabolites of C. ternatea will help to isolate the important phytoconstituents responsible for the central nervous system effects, isolated components can be utilized in future for the formulation of new medicine for various neurodegenerative disorders. In the present study, the phytochemical evaluation of the ethanolic root extract of C. ternatea (EECT) was performed using the HR-LCMS technique. Preliminary qualitative phytoconstituents analysis showed the presence of tannins, alkaloids, saponins, steroids, carbohydrate, protein, flavonoids and triterpenoids in the ethanolic root extract. Almost 42 compounds were identified when the EECT subjected to HR-LCMS analysis.

scholarly journals Identification and Characterization of Fusolisin, the Fusobacterium nucleatum Autotransporter Serine Protease

PLoS ONE ◽  
2014 ◽  
Vol 9 (10) ◽  
pp. e111329 ◽  
Author(s):  
Lior Doron ◽  
Shunit Coppenhagen-Glazer ◽  
Yara Ibrahim ◽  
Amir Eini ◽  
Ronit Naor ◽  
...  
Keyword(s):  
Serine Protease ◽  
Fusobacterium Nucleatum ◽  
Identification And Characterization

scholarly journals Identification and Characterization of the Phage Gene sav, Involved in Sensitivity to the Lactococcal Abortive Infection Mechanism AbiV

2009 ◽  
Vol 75 (8) ◽  
pp. 2484-2494 ◽  
Author(s):  
Jakob Haaber ◽  
Geneviève M. Rousseau ◽  
Karin Hammer ◽  
Sylvain Moineau
Keyword(s):  
Gel Filtration ◽  
Point Mutations ◽  
Whole Genome ◽  
Wild Type ◽  
Abortive Infection ◽  
Native Form ◽  
Phage Gene ◽  
Infection Mechanism ◽  
Identification And Characterization

ABSTRACT Lactococcus lactis phage mutants that are insensitive to the recently characterized abortive infection mechanism AbiV were isolated and analyzed in an effort to elucidate factors involved in the sensitivity to AbiV. Whole-genome sequencing of the phage mutants p2.1 and p2.2 revealed mutations in an orf that is transcribed early, indicating that this orf was responsible for AbiV sensitivity. Sequencing of the homologous regions in the genomes of other AbiV-insensitive mutants derived from p2 and six other lactococcal wild-type phages revealed point mutations in the homologous orf sequences. The orf was named sav (for sensitivity to AbiV), and the encoded polypeptide was named SaV. The purification of a His-tagged SaV polypeptide by gel filtration suggested that the polypeptide formed a dimer in its native form. The overexpression of SaV in L. lactis and Escherichia coli led to a rapid toxic effect. Conserved, evolutionarily related regions in SaV polypeptides of different phage groups are likely to be responsible for the AbiV-sensitive phenotype and the toxicity.

Glycosphingolipids of wild-type and mutant lectin-resistant Chinese hamster ovarian cells

1974 ◽  
Vol 56 (4) ◽  
pp. 1010-1016 ◽  
Author(s):  
G. Yogeeswaran ◽  
R.K. Murray ◽  
J.A. Wright
Keyword(s):  
Chinese Hamster ◽  
Wild Type ◽  
Ovarian Cells

scholarly journals Identification and Characterization of a Streptococcus pyogenes Operon Involved in Binding of Hemoproteins and Acquisition of Iron

2003 ◽  
Vol 71 (3) ◽  
pp. 1042-1055 ◽  
Author(s):  
Christopher S. Bates ◽  
Griselle E. Montañez ◽  
Charles R. Woods ◽  
Rebecca M. Vincent ◽  
Zehava Eichenbaum
Keyword(s):  
Hydrogen Peroxide ◽  
Streptococcus Pyogenes ◽  
Iron Acquisition ◽  
Iron Complex ◽  
Surface Proteins ◽  
Leader Peptide ◽  
Hemoglobin Binding ◽  
Membrane Bound ◽  
Identification And Characterization

ABSTRACT The hemolytic Streptococcus pyogenes can use a variety of heme compounds as an iron source. In this study, we investigate hemoprotein utilization by S. pyogenes. We demonstrate that surface proteins contribute to the binding of hemoproteins to S. pyogenes. We identify an ABC transporter from the iron complex family named sia for streptococcal iron acquisition, which consists of a lipoprotein (siaA), membrane permease (siaB), and ATPase (siaC). The sia transporter is part of a highly conserved, iron regulated, 10-gene operon. SiaA, which was localized to the cell membrane, could specifically bind hemoglobin. The operon's first gene encodes a novel bacterial protein that bound hemoglobin, myoglobin, heme-albumin, and hemoglobin-haptoglobin (but not apo-haptoglobin) and therefore was named Shr, for streptococcal hemoprotein receptor. PhoZ fusion and Western blot analysis showed that Shr has a leader peptide and is found in both membrane-bound and soluble forms. An M1 SF370 strain with a polar mutation in shr was more resistant to streptonigrin and hydrogen peroxide, suggesting decreased iron uptake. The addition of hemoglobin to the culture medium increased cell resistance to hydrogen peroxide in SF370 but not in the mutant, implying the sia operon may be involved in hemoglobin-dependent resistance to oxidative stress. The shr mutant demonstrated reduced hemoglobin binding, though cell growth in iron-depleted medium supplemented with hemoglobin, whole blood, or ferric citrate was not affected, suggesting additional systems are involved in hemoglobin utilization. SiaA and Shr are the first hemoprotein receptors identified in S. pyogenes; their possible role in iron capture is discussed.

scholarly journals Identification and Characterization of a New Lipoprotein, NlpI, in Escherichia coli K-12

1999 ◽  
Vol 181 (14) ◽  
pp. 4318-4325 ◽  
Author(s):  
Masaru Ohara ◽  
Henry C. Wu ◽  
Krishnan Sankaran ◽  
Paul D. Rick
Keyword(s):  
Escherichia Coli ◽  
Direct Consequence ◽  
Insertion Mutant ◽  
Polynucleotide Phosphorylase ◽  
Wild Type ◽  
E Coli ◽  
K 12 ◽  
Identification And Characterization ◽  
Lines Of Evidence

ABSTRACT We report here the identification of a new lipoprotein, NlpI, inEscherichia coli K-12. The NlpI structural gene (nlpI) is located between the genes pnp(polynucleotide phosphorylase) and deaD (RNA helicase) at 71 min on the E. coli chromosome. The nlpI gene encodes a putative polypeptide of approximately 34 kDa, and multiple lines of evidence clearly demonstrate that NlpI is indeed a lipoprotein. An nlpI::cm mutation rendered growth of the cells osmotically sensitive, and incubation of the insertion mutant at an elevated temperature resulted in the formation of filaments. The altered phenotype of the mutant was a direct consequence of the mutation in nlpI, since it was complemented by the wild-type nlpI gene alone. Overexpression of the unaltered nlpI gene in wild-type cells resulted in the loss of the rod morphology and the formation of single prolate ellipsoids and pairs of prolate ellipsoids joined by partial constrictions. NlpI may be important for an as-yet-undefined step in the overall process of cell division.

scholarly journals Identification and Characterization of a Determinant (eep) on the Enterococcus faecalisChromosome That Is Involved in Production of the Peptide Sex Pheromone cAD1

1999 ◽  
Vol 181 (19) ◽  
pp. 5915-5921 ◽  
Author(s):  
Florence Y. An ◽  
Mark C. Sulavik ◽  
Don B. Clewell
Keyword(s):  
Sex Pheromone ◽  
Wild Type ◽  
Mating Response ◽  
Enhanced Production ◽  
Precursor Structure ◽  
Enhanced Expression ◽  
Membrane Spanning ◽  
Identification And Characterization ◽  
Free Strains

ABSTRACT Plasmid-free strains of Enterococcus faecalis secrete a peptide sex pheromone, cAD1, which specifically induces a mating response by donors carrying the hemolysin plasmid pAD1 or related elements. A determinant on the E. faecalis OG1X chromosome has been found to encode a 46.5-kDa protein that plays an important role in the production of the extracellular cAD1. Wild-type E. faecalis OG1X cells harboring a plasmid chimera carrying the determinant exhibited an eightfold enhanced production of cAD1, and plasmid-free cells carrying a mutated chromosomal determinant secreted undetectable or very low amounts of the pheromone. The production of other pheromones such as cPD1, cOB1, and cCF10 was also influenced, although there was no effect on the pheromone cAM373. The determinant, designated eep (for enhanced expression of pheromone), did not include the sequence of the pheromone. Its deduced product (Eep) contains apparent membrane-spanning sequences; conceivably it is involved in processing a pheromone precursor structure or in some way regulates expression or secretion.

scholarly journals Identification and Characterization of a Phase-Variable Nonfimbrial Salmonella typhimurium Gene That Alters O-Antigen Production

1998 ◽  
Vol 66 (12) ◽  
pp. 5725-5730 ◽  
Author(s):  
Lola Y. Kwan ◽  
Richard E. Isaacson
Keyword(s):  
Salmonella Typhimurium ◽  
Phenotypic Switching ◽  
Phase Variable ◽  
Wild Type ◽  
Phagocytic Cells ◽  
Antigen Production ◽  
O Antigen ◽  
Identification And Characterization ◽  
Wild Type Parent

ABSTRACT Salmonella typhimurium 798, which was isolated from a pig, is known to phase vary from a nonadhesive to an adhesive phenotype. Cells of the adhesive phenotype adhere to porcine enterocytes, are more readily phagocytized by porcine neutrophils and macrophages, and once phagocytized can survive intracellularly, while cells of the nonadhesive phenotype die rapidly. The effect of phenotypic switching also can be visualized by changes in colony morphologies and the presence of between 10 and 15 proteins in the envelopes of cells in the adhesive phenotype. Mutants previously constructed with cells in the adhesive phenotype and the transposon TnphoA were screened to identify mutants lacking one or more of the unique proteins. One mutation was cloned and sequenced, and the mutation was shown to be in rfaL (O-antigen ligase). Expression of O antigen was shown to be phase variable. The adhesive strain expressed an O antigen that was at least eightfold longer than that for the nonadhesive strain and by virtue of O-antigen production was resistant to porcine complement. The mutant survived intracellularly in phagocytic cells as well as its wild-type parent.

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