scholarly journals Characterization of Two Campylobacter jejuni Strains for Use in Volunteer Experimental-Infection Studies

2008 ◽  
Vol 76 (12) ◽  
pp. 5655-5667 ◽  
Author(s):  
Frédéric Poly ◽  
Timothy D. Read ◽  
Yu-Han Chen ◽  
Mario A. Monteiro ◽  
Oralak Serichantalergs ◽  
...  
Keyword(s):  
Southeast Asia ◽  
Campylobacter Jejuni ◽  
Experimental Infection ◽  
Type Strain ◽  
Molecular Mimicry ◽  
Clinical Isolates ◽  
Capsule Locus ◽  
High Degree ◽  
Degree Of Similarity

ABSTRACT The development of vaccines against Campylobacter jejuni would be facilitated by the ability to perform phase II challenge studies. However, molecular mimicry of the lipooligosaccharide (LOS) of most C. jejuni strains with human gangliosides presents safety concerns about the development of Guillain-Barré syndrome. Clinical isolates of C. jejuni that appeared to lack genes for the synthesis of ganglioside mimics were identified by DNA probe analyses. Two clinical isolates from Southeast Asia (strains BH-01-0142 and CG8421) were determined to express the LOS type containing N-acetyl quinovosamine. No ganglioside structures were observed to be present in the LOSs of these strains, and pyrosequence analyses of the genomes of both strains confirmed the absence of genes involved in ganglioside mimicry. The capsule polysaccharide (CPS) of BH-01-0142 was determined to be composed of galactose (Gal), 6-deoxy-ido-heptose, and, in smaller amounts, d-glycero-d-ido-heptose, and the CPS of CG8421 was observed to contain Gal, 6-deoxy-altro-heptose, N-acetyl-glucosamine, and minor amounts of 6-deoxy-3-O-Me-altro-heptose. Both CPSs were shown to carry O-methyl-phosphoramidate. The two genomes contained strain-specific zones, some of which could be traced to a plasmid origin, and both contained a large chromosomal insertion related to the CJEI3 element of C. jejuni RM1221. The genomes of both strains shared a high degree of similarity to each other and, with the exception of the capsule locus of CG8421, to the type strain of the HS3 serotype, TGH9011.

scholarly journals Molecular characterization of Brazilian strains of Xanthomonas campestris pv. viticola by rep-PCR fingerprinting

2005 ◽  
Vol 30 (1) ◽  
pp. 46-54 ◽  
Author(s):  
Loiselene C. Trindade ◽  
Mirtes F. Lima ◽  
Marisa A. S. V. Ferreira
Keyword(s):  
Repetitive Dna ◽  
Type Strain ◽  
Xanthomonas Campestris ◽  
Geographic Location ◽  
Bacterial Canker ◽  
Bacterial Dna ◽  
High Degree ◽  
Genomic Patterns ◽  
Degree Of Similarity

Bacterial canker of grapevine (Vitis vinifera), caused by Xanthomonas campestris pv. viticola was first detected in Brazil in 1998, affecting grapevines in the São Francisco river basin, state of Pernambuco. The disease was also reported in Juazeiro, Bahia and later in Piauí and Ceará. Due to its limited geographical distribution and relatively recent detection in Brazil, very little is known about the pathogen's biology and diversity. Repetitive DNA based-PCR (rep-PCR) profiles were generated from purified bacterial DNA of 40 field strains of X. campestris pv. viticola, collected between 1998 and 2001 in the states of Pernambuco, Bahia and Piauí. Combined analysis of the PCR patterns obtained with primers REP, ERIC and BOX, showed a high degree of similarity among Brazilian strains and the Indian type strain NCPPB 2475. Similar genomic patterns with several diagnostic bands, present in all strains, could be detected. Fingerprints were distinct from those of strains representing other pathovars and from a yellow non-pathogenic isolate from grape leaves. The polymorphism observed among the Brazilian strains allowed their separation into five subgroups, although with no correlation with cultivar of origin, geographic location or year collected.

scholarly journals Molecular Characterization of S Locus Genes, SLG and SRK, in a Pollen-Recessive Self-Incompatibility Haplotype of Brassica rapa L

Genetics ◽  
1998 ◽  
Vol 149 (3) ◽  
pp. 1587-1597 ◽  
Author(s):  
Katsunori Hatakeyama ◽  
Takeshi Takasaki ◽  
Masao Watanabe ◽  
Kokichi Hinata
Keyword(s):  
Brassica Rapa ◽  
Genomic Dna ◽  
Transmembrane Domain ◽  
Brassica Species ◽  
Self Incompatibility ◽  
S Locus ◽  
Intron Sequence ◽  
High Degree ◽  
Degree Of Similarity

Abstract In Brassica species that exhibit self-incompatibility, two genes, SLG and SRK, at the S locus are involved in the recognition reaction with self and non-self pollen. From a pollen-recessive S29 haplotype of Brassica rapa, both cDNA and genomic DNA clones for these two genes were isolated and characterized. The nucleotide sequence for the S domain of SRK29 showed a high degree of similarity with that of SLG29, and they belong to Class II type. RNA gel blot analysis showed that the transcript of SLG29 consisted of the first and second exons, and no other transcript containing any part of the intron sequence was detected. Because no transmembrane domain was encoded by the second exon of SLG29, SLG29 was designated a secreted type glycoprotein. SLGs of two other pollen-recessive haplotypes, S40 and S44, of B. rapa also had a similar structure to that of SLG29. Previously, SLG2 from a pollen-recessive haplotype, S2, of Brassica oleracea was found to produce two different transcripts, one for the secreted type glycoprotein and the other for a putative membrane-anchored form of SLG. Therefore, the nature of these SLGs from pollen-recessive haplotypes of B. rapa is different from that of SLG2 of B. oleracea.

scholarly journals Characterization of the Duffy-Binding-Like Domain of Plasmodium falciparum Blood-Stage Antigen 332

2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Sandra Nilsson ◽  
Kirsten Moll ◽  
Davide Angeletti ◽  
Letusa Albrecht ◽  
Inari Kursula ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Immunofluorescence Microscopy ◽  
Homology Model ◽  
Cross Reactivity ◽  
Blood Stage ◽  
Conserved Domain ◽  
Erythrocyte Binding ◽  
High Degree ◽  
Degree Of Similarity

Studies on Pf332, a major Plasmodium falciparum blood-stage antigen, have largely been hampered by the cross-reactive nature of antibodies generated against the molecule due to its high content of repeats, which are present in other malaria antigens. We previously reported the identification of a conserved domain in Pf332 with a high degree of similarity to the Duffy-binding-like (DBL) domains of the erythrocyte-binding-like (EBL) family. We here describe that antibodies towards Pf332-DBL are induced after repeated exposure to P. falciparum and that they are acquired early in life in areas of intense malaria transmission. Furthermore, a homology model of Pf332-DBL was found to be similar to the structure of the EBL-DBLs. Despite their similarities, antibodies towards Pf332-DBL did not display any cross-reactivity with EBL-proteins as demonstrated by immunofluorescence microscopy, Western blotting, and peptide microarray. Thus the DBL domain is an attractive region to use in further studies on the giant Pf332 molecule.

scholarly journals Physicochemical and Biological Characterization of a Biosimilar Trastuzumab

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Carlos A. López-Morales ◽  
Mariana P. Miranda-Hernández ◽  
L. Carmina Juárez-Bayardo ◽  
Nancy D. Ramírez-Ibáñez ◽  
Alexis J. Romero-Díaz ◽  
...  
Keyword(s):  
Reference Product ◽  
World Health ◽  
Malignant Neoplasms ◽  
Pharmacological Studies ◽  
Comparability Exercise ◽  
Potential Impact ◽  
Health Organization ◽  
High Degree ◽  
Degree Of Similarity

According to the World Health Organization, the incidence of malignant neoplasms and endocrine, blood, and immune disorders will increase in the upcoming decades along with the demand of affordable treatments. In response to this need, the development of biosimilar drugs is increasing worldwide. The approval of biosimilars relies on the compliance with international guidelines, starting with the demonstration of similarity in their physicochemical and functional properties against the reference product. Subsequent clinical studies are performed to demonstrate similar pharmacological behavior and to diminish the uncertainty related to their safety and efficacy. Herein we present a comparability exercise between a biosimilar trastuzumab and its reference product, by using a hierarchical strategy with an orthogonal approach, to assess the physicochemical and biological attributes with potential impact on its pharmacokinetics, pharmacodynamics, and immunogenicity. Our results showed that the high degree of similarity in the physicochemical attributes of the biosimilar trastuzumab with respect to the reference product resulted in comparable biological activity, demonstrating that a controlled process is able to provide consistently the expected product. These results also constitute the basis for the design of subsequent delimited pharmacological studies, as they diminish the uncertainty of exhibiting different profiles.

scholarly journals Structural Characterization of Campylobacter jejuni Lipooligosaccharide Outer Cores Associated with Guillain-Barré and Miller Fisher Syndromes

2007 ◽  
Vol 75 (3) ◽  
pp. 1245-1254 ◽  
Author(s):  
Peggy C. R. Godschalk ◽  
Mark L. Kuijf ◽  
Jianjun Li ◽  
Frank St. Michael ◽  
C. Wim Ang ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Campylobacter Jejuni ◽  
Molecular Mimicry ◽  
Sequence Data ◽  
Outer Core ◽  
Ionization Mass ◽  
Fisher Syndrome ◽  
Disease Etiology ◽  
Dna Sequence Data

ABSTRACT Molecular mimicry between lipooligosaccharides (LOS) of Campylobacter jejuni and gangliosides in peripheral nerves plays a crucial role in the pathogenesis of C. jejuni-related Guillain-Barré syndrome (GBS). We have analyzed the LOS outer core structures of 26 C. jejuni strains associated with GBS and its variant, Miller Fisher syndrome (MFS), by capillary electrophoresis coupled with electrospray ionization mass spectrometry. Sixteen out of 22 (73%) GBS-associated and all 4 (100%) MFS-associated strains expressed LOS with ganglioside mimics. GM1a was the most prevalent ganglioside mimic in GBS-associated strains (10/22, 45%), and in eight of these strains, GM1a was found in combination with GD1a mimics. All seven strains isolated from patients with ophthalmoplegia (GBS or MFS) expressed disialylated (GD3 or GD1c) mimics. Three out of 22 GBS-associated strains (14%) did not express sialylated ganglioside mimics because their LOS locus lacked the genes necessary for sialylation. Three other strains (14%) did not express ganglioside mimics because of frameshift mutations in either the cstII sialyltransferase gene or the cgtB galactosyltransferase gene. It is not possible to determine if these mutations were already present during C. jejuni infection. This is the first report in which mass spectrometry combined with DNA sequence data were used to infer the LOS outer core structures of a large number of neuropathy-associated C. jejuni strains. We conclude that molecular mimicry between gangliosides and C. jejuni LOS is the presumable pathogenic mechanism in most cases of C. jejuni-related GBS. However, our findings suggest that in some cases, other mechanisms may play a role. Further examination of the disease etiology in these patients is mandatory.

scholarly journals Updated Campylobacter jejuni Capsule PCR Multiplex Typing System and Its Application to Clinical Isolates from South and Southeast Asia

PLoS ONE ◽  
2015 ◽  
Vol 10 (12) ◽  
pp. e0144349 ◽  
Author(s):  
Frédéric Poly ◽  
Oralak Serichantalergs ◽  
Janelle Kuroiwa ◽  
Piyarat Pootong ◽  
Carl Mason ◽  
...  
Keyword(s):  
Southeast Asia ◽  
Campylobacter Jejuni ◽  
Clinical Isolates ◽  
South And Southeast Asia ◽  
Pcr Multiplex ◽  
Typing System

scholarly journals Identification and characterization of Saccharomyces cerevisiae yapsin 3, a new member of the yapsin family of aspartic proteases encoded by the YPS3 gene

1999 ◽  
Vol 339 (2) ◽  
pp. 407-411 ◽  
Author(s):  
Vicki OLSEN ◽  
Niamh X. CAWLEY ◽  
Jakob BRANDT ◽  
Michi EGEL-MITANI ◽  
Y. Peng LOH
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Cleavage Sites ◽  
Basic Residue ◽  
Aspartic Proteases ◽  
N Terminus ◽  
High Degree ◽  
Identification And Characterization ◽  
Degree Of Similarity

A new aspartic protease from Saccharomyces cerevisiae, with a high degree of similarity with yapsin 1 and yapsin 2 and a specificity for basic residue cleavage sites of prohormones, has been cloned. This enzyme was named yapsin 3. Expression of a C-terminally truncated non-membrane anchored yapsin 3 in yeast yielded a heterogeneous protein between 135–200 kDa which, upon treatment with endoglycosidase H, migrated as a 60 kDa form. Amino-acid analysis of the N-terminus of expressed yapsin 3 revealed two different N-terminal residues, serine-48 and phenylalanine-54, which followed a dibasic and a monobasic residue respectively. Cleavage of several prohormones by non-anchored yapsin 3 revealed a specificity distinct from that of yapsin 1.

scholarly journals Molecular characterization of the honeybee Apis mellifera carnica in Serbia

2009 ◽  
Vol 61 (4) ◽  
pp. 587-598 ◽  
Author(s):  
N. Nedic ◽  
L. Stanisavljevic ◽  
M. Mladenovic ◽  
Jelena Stanisavljevic
Keyword(s):  
Comparative Analysis ◽  
Similarity Index ◽  
Phylogenetic Group ◽  
The Novel ◽  
Polymorphic Position ◽  
Queen Bees ◽  
Productive Traits ◽  
High Degree ◽  
Degree Of Similarity

The sequences COI-COII of the mitochondrial DNA region in honeybee from four geographically distant regions in Serbia (Vrsac, Knjazevac, Kraljevo, and Vranje) are analyzed. The research was conducted on eight different, previously selected honeybee lines preserved (linear selection) in the four reprocenters for queen bees. All four studied honeybee lines differ in morphological and productive traits, each being specific for the corresponding region. In addition to analysis of the mtDNA sequences in Serbian honeybee, a comparative analysis of the phylogenetic group of so far known C2 haplotypes was also performed. The results revealed two novel polymorphic positions in the COI-COII mtDNA region, viz., h2 at position 3474 and l2 at position 3534 (a T nucleotide deletion in both cases) in honeybees from the regions of Vranje and Knjazevac, respectively. Two novel mtDNA haplotypes in the honeybee C2 phylogenetic group, together with C2I (the new polymorphic position l2 and G-A transition at position 3587) and C2J (the new polymorphic position h2), are described. Also, comparative analysis performed on sequences from GenBank data showed a high degree of similarity (similarity index = 99.4%) between the novel C2I mtDNA haplotype and an A. m. cypria haplotype originating from Turkey. Certain domestic Kranjska honeybee populations from Serbia represent an autochthonous gene pool that can be of great importance for further presentation of honeybee biodiversity. The present paper contributes to characterization of mtDNA in honeybee of Serbia.

scholarly journals Relationships of capsular polysaccharides belonging to Campylobacter jejuni HS1 serotype complex

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0247305
Author(s):  
Mario A. Monteiro ◽  
Yu-Han Chen ◽  
Zuchao Ma ◽  
Cheryl P. Ewing ◽  
Nooraisyah Mohamad Nor ◽  
...  
Keyword(s):  
Campylobacter Jejuni ◽  
Type Strain ◽  
Teichoic Acid ◽  
Cross Reactivity ◽  
Capsular Polysaccharides ◽  
Common Component ◽  
Biosynthesis Gene ◽  
Capsule Locus ◽  
Common Serotypes ◽  
The Common

The Campylobacter jejuni capsule type HS1 complex is one of the most common serotypes identified worldwide, and consists of strains typing as HS1, HS1/44, HS44 and HS1/8. The capsule structure of the HS1 type strain was shown previously to be composed of teichoic-acid like glycerol-galactosyl phosphate repeats [4-)-α-D-Galp-(1–2)-Gro-(1-P-] with non-stoichiometric fructose branches at the C2 and C3 of Gal and non-stoichiometric methyl phosphoramidate (MeOPN) modifications on the C3 of the fructose. Here, we demonstrate that the capsule of an HS1/44 strain is identical to that of the type strain of HS1, and the capsule of HS1/8 is also identical to HS1, except for an additional site of MeOPN modification at C6 of Gal. The DNA sequence of the capsule locus of an HS44 strain included an insertion of 10 genes, and the strain expressed two capsules, one identical to the HS1 type strain, but with no fructose branches, and another composed of heptoses and MeOPN. We also characterize a HS1 capsule biosynthesis gene, HS1.08, as a fructose transferase responsible for the attachment of the β-D-fructofuranoses residues at C2 and C3 of the Gal unit. In summary, the common component of all members of the HS1 complex is the teichoic-acid like backbone that is likely responsible for the observed sero-cross reactivity.

scholarly journals Molecular Characterization of the GeneraProteus, Morganella, andProvidencia by Ribotyping

1999 ◽  
Vol 37 (9) ◽  
pp. 2840-2847 ◽  
Author(s):  
S. Pignato ◽  
G. M. Giammanco ◽  
F. Grimont ◽  
P. A. D. Grimont ◽  
G. Giammanco
Keyword(s):  
Molecular Characterization ◽  
Type Strain ◽  
Clinical Isolates ◽  
Rrna Gene ◽  
Restriction Patterns ◽  
Phenotypic Characters ◽  
Providencia Stuartii ◽  
Gene Restriction ◽  
Type Strains

The so-called Proteus-Providencia group is constituted at present by three genera and 10 species. Several of the recognized species are common opportunistic pathogens for humans and animals. Different methods based on the study of phenotypic characters have been used in the past with variable levels of efficiency for typing some species for epidemiological purposes. We have determined the rRNA gene restriction patterns (ribotypes) for the type strains of the 10 different species of the genera Proteus,Morganella, and Providencia. Visual inspection of EcoRV- and HincII-digested DNA from the type strains showed remarkably different patterns for both enzymes, butEcoRV provided better differentiation. Both endonucleases were retained to study a large number of wild and collection strains belonging to the different species. Clinical isolates of Proteus mirabilis, Proteus penneri, Morganella morganii, and Providencia heimbachae showed patterns identical or very similar to those of the respective type strains, so that groups of related patterns (ribogroups) were found to correspond to the diverse species. On the contrary, distinct ribogroups were detected within Providencia alcalifaciens (two ribogroups with both enzymes), Providencia rettgeri (four ribogroups with EcoRV and five with HincII),Providencia stuartii (two ribogroups withEcoRV), Providencia rustigianii (two ribogroups with HincII), and Proteus vulgaris (two ribogroups with both enzymes). The pattern shown by the ancientP. vulgaris type strain NCTC 4175 differed considerably from both P. vulgaris ribogroups as well as from the newly proposed type strain ATCC 29905 and from any other strain in this study, thus confirming its atypical nature. Minor differences were frequently observed among patterns of strains belonging to the same ribogroup. These differences were assumed to define ribotypes within each ribogroup. No correlation was observed between ribogroups or ribotypes and biogroups of P. vulgaris, P. alcalifaciens, P. stuartii, and P. rettgeri. Since, not only different species showed different rRNA gene restriction patterns, but also different ribogroups and ribotypes have been found in the majority of the species, ribotyping would be a sensitive method for molecular characterization of clinical isolates belonging to the genera Proteus, Morganella, and Providencia.

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