scholarly journals Development of a Molecular Serotyping Scheme for Morganella morganii

2021 ◽  
Vol 12 ◽  
Author(s):  
Bin Liu ◽  
Xi Guo ◽  
Jing Wang ◽  
Pan Wu ◽  
Shujie Li ◽  
...  
Keyword(s):  
High Specificity ◽  
Gene Clusters ◽  
Opportunistic Pathogen ◽  
Epidemiological Surveillance ◽  
Morganella Morganii ◽  
Bacterial Surface ◽  
Suspension Array ◽  
Molecular Serotyping ◽  
O Antigen ◽  
And Control

Morganella morganii, which is often regarded as a human commensal organism, can be an opportunistic pathogen, causing a variety of clinical infections with serious morbidity and mortality. An efficient and convenient method for subtyping and identifying M. morganii strains in epidemiological surveillance and control is urgently needed. Serotyping based on bacterial surface polysaccharide antigens (O-antigen or K-antigens) is a standard subtyping method for many gram-negative bacteria. Here, through whole genome sequencing and comparative genomics analysis of 27 strains, we developed a molecular serotyping scheme based on the genetic variation of O-antigen gene clusters (O-AGC) in M. morganii, and 11 distinct O-AGC types were identified. A conventional serotyping scheme was also developed by the production of antisera and agglutination experiments, which was shown to be perfectly consistent with the molecular serotyping scheme, confirming that the variation in M. morganii O-AGC correlated with phenotypic O-antigen diversification. Furthermore, a microsphere-based suspension array (MSA) with high specificity was developed based on the specific genes within each O-AGC type. The sensitivity of MSA was determined to be 0.1 ng of genomic DNA and 103 CFU of pure culture. We further analyzed 104 M. morganii genomes available in GenBank, and an additional six novel O-AGC types were identified, indicating that the extension of this molecular serotyping scheme is convenient. Our work provides an important tool for the detection and epidemiological surveillance of M. morganii, and this method has the potential to be widely utilized, especially for bacterial genera/species without an efficient typing approach.

scholarly journals The O28 Antigen Gene Clusters ofSalmonella entericasubsp.entericaSerovar Dakar and Serovar Pomona Are Different

2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Clifford G. Clark ◽  
Christopher C. R. Grant ◽  
Keri M. Trout-Yakel ◽  
Helen Tabor ◽  
Lai-King Ng ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Salmonella Enterica ◽  
Reference Strain ◽  
Gene Clusters ◽  
Correct Interpretation ◽  
Antigen Gene ◽  
Molecular Serotyping ◽  
O Antigen

A 10 kb O-antigen gene cluster was sequenced from aSalmonella entericasubsp.entericaDakar O28 reference strain and from twoS. Pomona serogroup O28 isolates. The twoS. Pomona O antigen gene clusters showed only moderate identity with theS. Dakar O28 gene cluster, suggesting that the O antigen oligosaccharides may contain one or more sugars conferring the O28 epitope but may otherwise be different. These novel findings are absolutely critical for the correct interpretation of molecular serotyping assays targeting genes within the O antigen gene clusters of theseSalmonellaserotypes and suggest the possibility that the O antigen gene clusters of otherSalmonellaserovars may also be heterogenous.

scholarly journals Development of an O-Antigen Serotyping Scheme forCronobacter sakazakii

2011 ◽  
Vol 77 (7) ◽  
pp. 2209-2214 ◽  
Author(s):  
Yamin Sun ◽  
Min Wang ◽  
Hongbo Liu ◽  
Jingjing Wang ◽  
Xin He ◽  
...  
Keyword(s):  
Fragment Length Polymorphism ◽  
Gene Clusters ◽  
Opportunistic Pathogen ◽  
Cronobacter Sakazakii ◽  
Bacterial Strains ◽  
Banding Patterns ◽  
O Antigen ◽  
Severe Infections ◽  
O Antigens ◽  
Restriction Fragment Length

ABSTRACTCronobacter sakazakiiis an opportunistic pathogen that can cause severe infections. Serotyping provides a basis for the categorization of bacterial strains and is an important tool for epidemiological and surveillance purposes. In this study, of the 135Cronobacterstrains tested initially, 119 were identified asC. sakazakiiand used. A serotyping scheme forC. sakazakiithat classifies strains based on their different O antigens was developed. Seven antisera that exhibited high agglutinin titers (>640) were produced. O2 and O6 antisera were specific for their homologous strains, O4 and O7 antisera gave heterologous titers with O1 and O6 antigens, respectively, and O1, O3, and O5 antisera cross-reacted with each other and require preabsorption with the other two antigens. All of these 119C. sakazakiistrains were clearly assigned to these seven serotypes. O1 and O2 are the dominant serotypes, comprising 69.7% of the isolates. We also characterized the O-antigen gene clusters using restriction fragment length polymorphism (RFLP). The grouping ofC. sakazakiistrains based on their RFLP banding patterns correlated well with the grouping of strains based on our serotyping scheme. The serotype scheme presented here could prove to be a useful tool for serotypingC. sakazakiiisolates.

The Estimation of prostate specific antigen (PSA) concentrations in patients with prostatitis by fully automated ELISA technique.

2020 ◽  
Vol 3 (11) ◽  
pp. 1100-1104
Author(s):  
Hussein Naeem Aldhaheri ◽  
Ihsan Edan AlSaimary ◽  
Murtadha Mohammed ALMusafer
Keyword(s):  
Personal Information ◽  
Receptor Gene ◽  
Specific Antigen ◽  
Gene Clusters ◽  
Control Group ◽  
P Value ◽  
Group Data ◽  
Elisa Technique ◽  
And Control

      The Aim of this study was to determine Immunogenetic expression of  Toll-like receptor gene clusters related to prostatitis, to give acknowledge about Role of TLR in prostatitis immunity in men from Basrah and Maysan provinces. A case–control study included 135 confirmed prostatitis patients And 50 persons as a control group. Data about age, marital status, working, infertility, family history and personal information like (Infection, Allergy, Steroid therapy, Residency, Smoking, Alcohol Drinking, Blood group, Body max index (BMI) and the clinical finding for all patients of Prostatitis were collected. This study shows the effect of PSA level in patients with prostatitis and control group, with P-value <0.0001 therefore the study shows a positive significant between elevated PSA levels and Prostatitis.

scholarly journals Mutational analysis of genes implicated in LPS and capsular polysaccharide biosynthesis in the opportunistic pathogen Bacteroides fragilis

Microbiology ◽  
2009 ◽  
Vol 155 (4) ◽  
pp. 1039-1049 ◽  
Author(s):  
Sheila Patrick ◽  
Simon Houston ◽  
Zubin Thacker ◽  
Garry W. Blakely
Keyword(s):  
Capsular Polysaccharide ◽  
Mutational Analysis ◽  
Bacteroides Fragilis ◽  
Gene Clusters ◽  
Opportunistic Pathogen ◽  
Extracellular Polysaccharides ◽  
Phase Variable ◽  
Multiple Gene ◽  
Polysaccharide Biosynthesis ◽  
Group 1

The obligate anaerobe Bacteroides fragilis is a normal resident of the human gastrointestinal tract. The clinically derived B. fragilis strain NCTC 9343 produces an extensive array of extracellular polysaccharides (EPS), including antigenically distinct large, small and micro- capsules. The genome of NCTC 9343 encodes multiple gene clusters potentially involved in the biosynthesis of EPS, eight of which are implicated in production of the antigenically variable micro-capsule. We have developed a rapid and robust method for generating marked and markerless deletions, together with efficient electroporation using unmodified plasmid DNA to enable complementation of mutations. We show that deletion of a putative wzz homologue prevents production of high-molecular-mass polysaccharides (HMMPS), which form the micro-capsule. This observation suggests that micro-capsule HMMPS constitute the distal component of LPS in B. fragilis. The long chain length of this polysaccharide is strikingly different from classical enteric O-antigen, which consists of short-chain polysaccharides. We also demonstrate that deletion of a putative wbaP homologue prevents expression of the phase-variable large capsule and that expression can be restored by complementation. This suggests that synthesis of the large capsule is mechanistically equivalent to production of Escherichia coli group 1 and 4 capsules.

scholarly journals Dienogest exerts its anti-endometriotic effect throughthe direct suppression of matrix metallopeptidases

2020 ◽  
Author(s):  
Hiroshi Honda ◽  
Norihisa Nishimichi ◽  
Michinori Yamashita ◽  
Yumiko Akimoto ◽  
Hirotoshi Tanimoto ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Group Versus ◽  
Gene Expression Profiles ◽  
High Specificity ◽  
Reproductive Age ◽  
Control Group ◽  
Canonical Pathways ◽  
Hormonal Therapies ◽  
And Control ◽  
Direct Suppression

Abstract Background: Endometriosis, which affects up to 10% women of reproductive age, is defined by the presence of ectopic endometrial tissue outside the uterus. The current key drug of hormonal therapies for endometriosis is dienogest, which is a progestin with high specificity for the progesterone receptor. Although many findings about the anti-endometriotic effect of dienogest on endometriosis have been reported, the precise mechanisms of dienogest's anti-endometriotic effect remain unknown. Methods: To investigate the direct anti-endometriotic effect of dienogest on endometriotic cells, we determined and compared the genome-wide gene expression profiles of endometriotic stromal cells treated with dienogest (Dienogest group) and those not treated with dienogest (Control group) and then performed a pathway analysis using these data. To test the microarray data, we performed real-time RT-PCRs for matrix metallopeptidase (MMP)-1, MMP-3, MMP-10, and TIMP-4.Results: Six-hundred forty-seven genes were revealed to be differentially expressed between the Dienogest and Control groups. Of them, 314 genes were upregulated and 333 genes were downregulated in the Dienogest group compared to the Control group. We identified 20 canonical pathways that are significantly distinct in the Dienogest group versus the Control group. Among the 20 canonical pathways, MMPs including MMP-1, -3, and -10 were found to be the most involved genes. Conclusions: Our results suggest that dienogest may exert its anti-endometriotic effect through the direct suppression of MMPs.

scholarly journals Heterogeneous expression of Pil3 pilus is critical for Streptococcus gallolyticus translocation across polarized colonic epithelial monolayers

2019 ◽  
Author(s):  
Mariana Martins ◽  
Laurence du Merle ◽  
Patrick Trieu-Cuot ◽  
Shaynoor Dramsi
Keyword(s):  
Intestinal Barrier ◽  
Opportunistic Pathogen ◽  
Oral Route ◽  
Elderly Persons ◽  
Dependent Manner ◽  
Bacterial Surface ◽  
Streptococcus Gallolyticus ◽  
Heterogeneous Expression ◽  
Colonic Cells

ABSTRACTStreptococcus gallolyticus subspecies gallolyticus (Sgg) is an opportunistic pathogen responsible for septicaemia and endocarditis in elderly persons. Sgg is also a commensal of the human gastrointestinal tract. Here we demonstrate that Sgg strain UCN34 translocates across tight intestinal barriers in vitro in a Pil3-dependent manner. Confocal images of UCN34 passage across human colonic cells reveals that Sgg utilizes a paracellular pathway. Pil3 was previously shown to be expressed heterogeneously and WT UCN34 consists of about 90% of Pil3low and 10% of Pil3high cells. We found that both the Δpil3 mutant and the Pil3+ overexpressing variant could not translocate across Caco-2 and T84 barriers. Interestingly, combining live Δpil3 mutant cells with fixed Pil3+ variants in a 10:1 ratio (mimicking UCN34 WT population) allowed efficient translocation of the Δpil3 mutant. These experiments demonstrate that heterogeneous expression of Pil3 plays a key role in optimal translocation of Sgg across the intestinal barrier.ABSTRACT IMPORTANCEStreptococcus gallolyticus subsp. gallolyticus (Sgg) is an opportunistic pathogen responsible for septicemia and infective endocarditis in elderly persons. Sgg is a commensal of the rumen of herbivores and transmission to humans most probably occurs through the oral route. In this work, we have studied how this bacterium crosses the intestinal barrier using well-known in vitro models. Confocal microscopy images revealed that Sgg UCN34 can traverse the epithelial monolayer in between adjacent cells. We next showed that passage of Sgg from the apical to the basolateral compartment is dependent on the heterogenous expression of the Pil3 pilus at the bacterial surface. We hypothesize that Pil3high cocci adhere firmly to epithelial cells to activate transient opening of tight junctions thereby allowing the traversal of Pil3low bacteria.

scholarly journals An Algerian perspective on non-typhoidal Salmonella infection

2017 ◽  
Vol 11 (08) ◽  
pp. 583-590
Author(s):  
Bilal Djeghout ◽  
Ammar Ayachi ◽  
Bianca Paglietti ◽  
Gemma C. Langridge ◽  
Salvatore Rubino
Keyword(s):  
Antimicrobial Treatment ◽  
Epidemiological Surveillance ◽  
Health Concern ◽  
Surveillance Systems ◽  
Global Public Health ◽  
Major Health ◽  
Salmonella Infections ◽  
Food Animal ◽  
Food Borne ◽  
And Control

Non-typhoidal Salmonella (NTS) represents a leading cause of food-borne disease worldwide. It is a global public health concern: more than 94 million cases and 115,000 deaths are reported every year, with a disproportionate impact in developing countries. The prevalence of multi-drug-resistant (MDR) Salmonella strains is another major health concern which affects antimicrobial treatment, as many studies report that infections caused by MDR strains are more severe than those caused by susceptible strains. In Algeria, NTS represent one of the primary causes of salmonellosis in both humans and food animal production, especially poultry. Epidemiological surveillance systems and monitoring programs for Salmonella infections are essential requirements to provide data useful for the effective detection and control of Salmonella outbreaks. The present review will supply a perspective on NTS infection, pathogenesis and antimicrobial resistance with a focus on the epidemiology of salmonellosis in Algeria.

scholarly journals A Novel Method of Serum Resistance by Escherichia coli That Causes Urosepsis

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Carrie F. Coggon ◽  
Andrew Jiang ◽  
Kelvin G. K. Goh ◽  
Ian R. Henderson ◽  
Mark A. Schembri ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Serum Resistance ◽  
Gram Negative ◽  
Content Type ◽  
Bacterial Surface ◽  
O Antigen ◽  
High Prevalence ◽  
Novel Method ◽  
Inhibitory Antibodies

ABSTRACT Uropathogenic Escherichia coli (UPEC) is the most common cause of urinary tract infection, which in some patients can develop into life-threatening urosepsis. Serum resistance is a key virulence trait of strains that cause urosepsis. Recently, we identified a novel method of serum resistance in patients with Pseudomonas aeruginosa lung infections, where patients possessed antibodies that inhibited complement-mediated killing (instead of protecting against infection). These inhibitory antibodies were of the IgG2 subtype, specific to the O-antigen component of lipopolysaccharide (LPS) and coated the bacterial surface, preventing bacterial lysis by complement. As this mechanism could apply to any Gram-negative bacterial infection, we hypothesized that inhibitory antibodies may represent an uncharacterized mechanism of serum resistance in UPEC. To test this, 45 urosepsis patients with paired blood culture UPEC isolates were screened for serum titers of IgG2 specific for their cognate strain’s LPS. Eleven patients had sufficiently high titers of the antibody to inhibit serum-mediated killing of UPEC isolates by pooled healthy control sera. Depletion of IgG or removal of O-antigen restored sensitivity of the isolates to the cognate patient serum. Importantly, the isolates from these 11 patients were more sensitive to killing by serum than isolates from patients with no inhibitory antibodies. This suggests the presence of inhibitory antibodies may have allowed these strains to infect the bloodstream. The high prevalence of patients with inhibitory antibodies (24%) suggests that this phenomenon is an important mechanism of UPEC serum resistance. LPS-specific inhibitory antibodies have now been identified against three Gram-negative pathogens that cause disparate diseases. IMPORTANCE Despite improvements in the early detection and management of sepsis, morbidity and mortality are still high. Infections of the urinary tract are one of the most frequent sources of sepsis with Escherichia coli the main causative agent. Serum resistance is vital for bacteria to infect the bloodstream. Here we report a novel method of serum resistance found in patients with UPEC-mediated sepsis. Antibodies in sera usually protect against infection, but here we found that 24% of patients expressed “inhibitory antibodies” capable of preventing serum-mediated killing of their infecting isolate. Our data suggest that these antibodies would allow otherwise serum-sensitive UPEC strains to cause sepsis. The high prevalence of patients with inhibitory antibodies in this cohort suggests that this is a widespread mechanism of resistance to complement-mediated killing in urosepsis patients, invoking the potential for the application of new methods to prevent and treat sepsis.

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