Wide Distribution of Virulence Genes amongEnterococcus faeciumandEnterococcus faecalisClinical Isolates

Enterococcus, a Gram-positive facultative anaerobic cocci belonging to the lactic acid bacteria of the phylum Firmicutes, is known to be able to resist a wide range of hostile conditions such as different pH levels, high concentration of NaCl (6.5%), and the extended temperatures between 5°C and 65°C. Despite being the third most common nosocomial pathogen, our understanding on its virulence factors is still poorly understood. The current study was aimed to determine the prevalence of different virulence genes inEnterococcus faecalisandEnterococcus faecium. For this purpose, 79 clinical isolates of Malaysian enterococci were evaluated for the presence of virulence genes.pilB, fms8, efaAfm, andsgrAgenes are prevalent in all clinical isolates. In conclusion, the pathogenicity ofE. faecalisandE. faeciumcould be associated with different virulence factors and these genes are widely distributed among the enterococcal species.

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Analysis of virulence factors and emm typing of Streptococcus pyogenes clinical isolates.

10.7287/peerj.preprints.27649v1 ◽

2019 ◽

Author(s):

Gustavo Enck Sambrano ◽

Gustavo P Riboldi ◽

Keli C Reiter ◽

Thiago Galvão da Silva Paim ◽

Neidmar Correa Tolfo ◽

...

Keyword(s):

Virulence Factors ◽

Streptococcus Pyogenes ◽

Virulence Genes ◽

Clinical Isolates ◽

Pcr Analysis ◽

Tissue Tropism ◽

Factors Analysis ◽

Wide Range ◽

Group A ◽

Micro Organisms

Background: Streptococcus pyogenes, a Group A streptococci (GAS), is an important human pathogen that causes a wide range of infections. Methods: Twenty five clinical isolates of S. pyogenes were submitted to an emm typing and to a Real-time PCR analysis for 23 important virulence factors. Results: Fourteen emm types were found and the emm1 type was the most prevalent. The majority of the isolates were classified as emm pattern E, followed by A-C3. No pattern D was found. Among the virulence factors, the most prevalent were SpeG, Slo, C5a-peptidase and SPNA. Phage encoded virulence genes were also found among the strains, such as mf-2, SpeJ and SpeL. Discussion: The emm1 type was the most prevalent while the 13 others M types were distributed along the strains. No tissue tropism was found on the isolates. The virulence factors analysis demonstrated that chromosomally and phage-encoded genes were found, which confers a potential for high virulent micro-organisms.

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Analysis of virulence factors and emm typing of Streptococcus pyogenes clinical isolates.

10.7287/peerj.preprints.27649 ◽

2019 ◽

Author(s):

Gustavo Enck Sambrano ◽

Gustavo P Riboldi ◽

Keli C Reiter ◽

Thiago Galvão da Silva Paim ◽

Neidmar Correa Tolfo ◽

...

Keyword(s):

Virulence Factors ◽

Streptococcus Pyogenes ◽

Virulence Genes ◽

Clinical Isolates ◽

Pcr Analysis ◽

Tissue Tropism ◽

Factors Analysis ◽

Wide Range ◽

Group A ◽

Micro Organisms

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Virulence Factors Associated with Pediatric Shigellosis in Brazilian Amazon

BioMed Research International ◽

10.1155/2014/539697 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 15

Author(s):

Carolinie Batista Nobre da Cruz ◽

Maria Carolina Scheffer de Souza ◽

Paula Taquita Serra ◽

Ivanildes Santos ◽

Antonio Balieiro ◽

...

Keyword(s):

Human Health ◽

Virulence Factors ◽

Health Problem ◽

Virulence Genes ◽

Bacillary Dysentery ◽

Brazilian Amazon ◽

Clinical Isolates ◽

Pathogenic Potential ◽

Factors Associated ◽

Etiologic Study

Shigellosis is a global human health problem and the incidence is highest among children. In the present work, mainShigellavirulence genes was examined by PCR and compared to symptoms of pediatric shigellosis. ThirtyShigellaisolates were identified from an etiologic study at which 1,339 children ranging 0–10 years old were enrolled.S. flexneriwas the most frequent species reaching 60.0% of isolates, 22.2% wereS. sonnei, and 6.6% were bothS. dysenteriaeandS. boydii. AllShigellainfected children had diarrhea, but not all were accompanied by others symptoms of bacillary dysentery. Among major virulence genes, the PCR typing revealedipaBCDwas present in all isolates, followed byIpaH7.8,set-1A,set-1B, sen/ospD3, virF,andinvE. The pathogenic potential of the ShET-1B subunit was observed in relation to dehydration (P<0.001) and ShET-2 related to the intestinal injury (P=0.033) evidenced by the presence of bloody diarrhea. Our results show associations among symptoms of shigellosis and virulence genes of clinical isolates ofShigellaspp.

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Virulence Gene Pattern of Pasteurella multocida Isolates of Buffalo in Association to Capsule Biosynthesis Genes

Indian Journal of Animal Research ◽

10.18805/ijar.b-3977 ◽

2020 ◽

Author(s):

N. Sujatha ◽

K. Lakshmi Kavitha ◽

K.V. Subramanyam ◽

T. Srinivasa Rao ◽

R.N. Ramani Pushpa

Keyword(s):

Virulence Factors ◽

Pasteurella Multocida ◽

Virulence Genes ◽

Systemic Disease ◽

Virulence Gene ◽

Disease Status ◽

Host Cells ◽

Wide Range ◽

Serotype B ◽

Apparently Healthy

Background: Pasteurella multocida is the causative agent of many economically important diseases in a wide range of hosts. The mechanisms by which these bacteria can invade the mucosa, evade innate immunity and cause systemic disease are slowly being elucidated. Many key virulence factors are yet to be identified, including those required for initial attachment and invasion of host cells and for persistence in a relatively nutrient poor and hostile environment. This has led to intensive research to understand host adaptation mechanisms and virulence factors in order to develop effective vaccines. Methods: The present study was carried out to know the distribution of virulence genes viz., haemoglobin binding proteins (hgbA and hgbB), outer membrane protein (ompH), fimbrial antigen (ptfA), filamentous haemagglutinin (pfhA) and transferrin binding protein (tbpA) by PCR in P. multocida CapA isolates from apparently healthy or carrier animals and CapB isolates from field Haemorrhagic septicemia (HS) cases to monitor the epidemiological associations of virulence genes in Cap A and Cap B isolates.Result: The study revealed that all the six virulence associated genes were present in Cap B isolates. None of the Cap A isolates harboured tbpA and pfhA genes. These two genes were closely related to serotype B causing Haemorrhagic septicemia and were epidemiologically associated with disease status.

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Whole Genome Sequence Analysis of Brucella melitensis Phylogeny and Virulence Factors

Microbiology Research ◽

10.3390/microbiolres12030050 ◽

2021 ◽

Vol 12 (3) ◽

pp. 698-710

Author(s):

Peter Rabinowitz ◽

Bar Zilberman ◽

Yair Motro ◽

Marilyn C. Roberts ◽

Alex Greninger ◽

...

Keyword(s):

Virulence Factors ◽

Pathogenic Bacteria ◽

Virulence Genes ◽

Brucella Melitensis ◽

Geographic Region ◽

Clinical Severity ◽

Whole Genome Sequence ◽

Whole Genome ◽

Pan Genome ◽

Wide Range

Brucellosis has a wide range of clinical severity in humans that remains poorly understood. Whole genome sequencing (WGS) analysis may be able to detect variation in virulence genes. We used Brucella melitensis sequences in the NCBI Sequence Read Archive (SRA) database to assemble 248 whole genomes, and additionally, assembled 27 B. melitensis genomes from samples of human patients in Southern Israel. We searched the 275 assembled genomes for the 43 B. melitensis virulence genes in the Virulence Factors of Pathogenic Bacteria Database (VFDB) and 10 other published putative virulence genes. We explored pan-genome variation across the genomes and in a pilot analysis, explored single nucleotide polymorphism (SNP) variation among the ten putative virulence genes. More than 99% of the genomes had sequences for all Brucella melitensis virulence genes included in the VFDB. The 10 other virulence genes of interest were present across all the genomes, but three of these genes had SNP variation associated with particular Brucella melitensis genotypes. SNP variation was also seen within the Israeli genomes obtained from a small geographic region. While the Brucella genome is highly conserved, this novel and large whole genome study of Brucella demonstrates the ability of whole genome and pan-genome analysis to screen multiple genomes and identify SNP variation in both known and novel virulence genes that could be associated with differential disease virulence. Further development of whole genome techniques and linkage with clinical metadata on disease outcomes could shed light on whether such variation in the Brucella genome plays a role in pathogenesis.

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Characterization and Genetic Diversity of Listeria monocytogenes Isolated from Cattle Abortions in Latvia, 2013–2018

Veterinary Sciences ◽

10.3390/vetsci8090195 ◽

2021 ◽

Vol 8 (9) ◽

pp. 195

Author(s):

Žanete Šteingolde ◽

Irēna Meistere ◽

Jeļena Avsejenko ◽

Juris Ķibilds ◽

Ieva Bergšpica ◽

...

Keyword(s):

Genetic Diversity ◽

Listeria Monocytogenes ◽

Virulence Factors ◽

Causative Agent ◽

Animal Species ◽

Clonal Complex ◽

The Third ◽

Wide Range ◽

Sequence Types

Listeria monocytogenes can cause disease in humans and in a wide range of animal species, especially in farm ruminants. The aim of the study was to determine the prevalence and genetic diversity of L. monocytogenes related to 1185 cattle abortion cases in Latvia during 2013–2018. The prevalence of L. monocytogenes among cattle abortions was 16.1% (191/1185). The seasonality of L. monocytogenes abortions was observed with significantly higher occurrence (p < 0.01) in spring (March–May). In 61.0% of the cases, the affected cattle were under four years of age. L. monocytogenes abortions were observed during the third (64.6%) and second (33.3%) trimesters of gestation. Overall, 27 different sequence types (ST) were detected, and four of them, ST29 (clonal complex, CC29), ST37 (CC37), ST451 (CC11) and ST7 (CC7), covered more than half of the L. monocytogenes isolates. Key virulence factors like the prfA-dependent virulence cluster and inlA, inlB were observed in all the analyzed isolates, but lntA, inlF, inlJ, vip were associated with individual sequence types. Our results confirmed that L. monocytogenes is the most important causative agent of cattle abortions in Latvia and more than 20 different STs were observed in L. monocytogenes abortions in cattle.

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Carbapenem Resistance Profiles of Pathogenic Escherichia coli in Uganda

European Journal of Biology and Biotechnology ◽

10.24018/ejbio.2021.2.2.171 ◽

2021 ◽

Vol 2 (2) ◽

pp. 63-73

Author(s):

Kenneth Ssekatawa ◽

Denis K. Byarugaba ◽

Jesca L. Nakavuma ◽

Charles D. Kato ◽

Francis Ejobi ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Factors ◽

Virulence Genes ◽

Carbapenem Resistance ◽

Phylogenetic Group ◽

Clinical Isolates ◽

Phylogenetic Groups ◽

Phenotypic Resistance ◽

E Coli ◽

Tract Infections

Escherichia coli has been implicated as one of the main etiological agents of diarrhea, urinary tract infections, meningitis and septicemia worldwide. The ability to cause diseases is potentiated by presence of virulence factors. The virulence factors influence the capacity of E. coli to infect and colonize different body systems. Thus, pathogenic E. coli are grouped into DEC strains that are mainly clustered in phylogenetic group B1 and A; ExPEC belonging to A, B2 and D. Coexistence of virulence and beta-lactamase encoding genes complicates treatment outcomes. Therefore, this study aimed at presenting the carbapenem resistance (CR) profiles among pathogenic E. coli. This was a retrospective cross-sectional study involving use of 421 archived E. coli clinical isolates collected in 2019 from four Uganda tertiary hospitals. The isolates were subjected to antibiotics sensitivity assays to determine phenotypic resistance. Four sets of multiplex PCR were performed to detect CR genes, DEC pathotypes virulence genes, ExPEC PAI and the E. coli phylogenetic groups. Antibiotic susceptibility revealed that all the 421 E. coli isolates used were MDR as they exhibited 100% resistance to more than one of the first-line antibiotics. The study registered phenotypic and genotypic CR prevalence of 22.8% and 33.0% respectively. The most predominant gene was blaOXA-48 with genotypic frequency of 33.0%, then blaVIM (21.0%), blaIMP (16.5%), blaKPC (14.8%) and blaNDM (14.8%). Spearman’s correlation revealed that presence of CR genes was highly associated with phenotypic resistance. Furthermore, of 421 MDR E. coli isolates, 19.7% harboured DEC virulence genes, where EPEC recorded significantly higher prevalence (10.8%) followed by S-ETEC (3.1%), STEC (2.9%), EIEC (2.0%) and L-ETEC (2.0%). Genetic analysis characterized 46.1% of the isolates as ExPEC and only PAI IV536 (33.0%) and PAI IICFT073 (13.1%) were detected. Phylogenetic group B2 was predominantly detected (41.1%), followed by A (30.2%), B1(21.6%), and D (7.1%). Furthermore, 38.6% and 23.1% of the DEC and ExPEC respectively expressed phenotypic resistance. Our results exhibited significant level of CR carriage among the MDR DEC and ExPEC clinical isolates belonging to phylogenetic groups B1 and B2 respectively. Virulence and CR genetic factors are mainly located on mobile elements. Thus, constitutes a great threat to the healthcare system as this promotes horizontal gene transfer.

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Listeria monocytogenes Response to Anaerobic Environments

Pathogens ◽

10.3390/pathogens9030210 ◽

2020 ◽

Vol 9 (3) ◽

pp. 210 ◽

Cited By ~ 3

Author(s):

Brandy N. Roberts ◽

Damayanti Chakravarty ◽

J.C. Gardner ◽

Steven C. Ricke ◽

Janet R. Donaldson

Keyword(s):

Listeria Monocytogenes ◽

Food Processing ◽

Dairy Products ◽

Anaerobic Bacterium ◽

Virulence Genes ◽

Impact Resistance ◽

The Elderly ◽

Anaerobic Conditions ◽

Wide Range ◽

Facultative Anaerobic

Listeria monocytogenes is a Gram-positive facultative anaerobic bacterium that is responsible for the disease, listeriosis. It is particularly lethal in pregnant women, the fetus, the elderly and the immunocompromised. The pathogen survives and replicates over a wide range of temperatures (4 to 42 °C), pH, salt and oxygen concentrations. Because it can withstand various environments, L. monocytogenes is a major concern in food processing industries, especially in dairy products and ready-to-eat fruits, vegetables and deli meats. The environment in which the pathogen is exposed can influence the expression of virulence genes. For instance, studies have shown that variations in oxygen availability can impact resistance to stressors. Further investigation is needed to understand the essential genes required for the growth of L. monocytogenes in anaerobic conditions. Therefore, the purpose of this review is to highlight the data on L. monocytogenes under known environmental stresses in anaerobic environments and to focus on gaps in knowledge that may be advantageous to study in order to better understand the pathogenicity of the bacterium.

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Distinction between Antimicrobial Resistance and Putative Virulence Genes Characterization in Plesiomonas shigelloides Isolated from Different Sources

Antibiotics ◽

10.3390/antibiotics11010085 ◽

2022 ◽

Vol 11 (1) ◽

pp. 85

Author(s):

Samy Selim ◽

Mohammed S. Almuhayawi ◽

Shadi Ahmed Zakai ◽

Ahmed Attia Salama ◽

Mona Warrad

Keyword(s):

Antimicrobial Resistance ◽

Bacterial Infection ◽

Virulence Factors ◽

Virulence Genes ◽

Aquatic Habitats ◽

Gram Negative ◽

Plesiomonas Shigelloides ◽

Wide Range ◽

Different Sources ◽

Human Stool

Plesiomonas shigelloides are gram-negative, thermotolerant, motile, and pleomorphic microorganisms that are only distantly related to those of the Enterobacteriaceae and Vibrionaceae families. One of the most common sources of P. shigelloides contamination is human stool, but it may also be found in a wide range of other animals, plants, and aquatic habitats. Antimicrobial resistance in P. shigelloides from seawater and shellfish was investigated, and pathogenicity involved genes were characterized as part of this study. Out of 384 samples of shellfish, 5.7% included P. shigelloides. The presence of P. shigelloides was also discovered in 5% of the seawater sampled. The antimicrobial resistance of 23 P. shigelloides isolates derived from those samples was investigated. All isolates were sensitive to nalidixic acid, carbenicillin, cephalothin, erythromycin, kanamycin, tetracycline, and ciprofloxacin in the study. Several strains isolated from diseased shellfish were tested for virulence in shellfish by intraperitoneal injections. The LD50 values ranged from 12 × 108 to 3 × 1012 cfu/shellfish. When looking for possible virulence factors that may play a significant role in bacterial infection in the current study, we found that all of these genes were present in these strains. These include genes such as elastase, lipase, flagellin, enterotoxin, and DNases. According to these findings, shellfish may serve as a reservoir for multi-resistant P. shigelloides and help spread virulence genes across the environment.

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The Colonial Documentary Film in South and South-East Asia

10.3366/edinburgh/9781474407205.001.0001 ◽

2017 ◽

Keyword(s):

East Asia ◽

Subject Matter ◽

Documentary Film ◽

East Asian ◽

South East Asia ◽

Post Colonial ◽

Historical Perspectives ◽

The Third ◽

Wide Range ◽

Global Understanding

Writing from a wide range of historical perspectives, contributors to the anthology shed new light on historical, theoretical and empirical issues pertaining to the documentary film, in order to better comprehend the significant transformations of the form in colonial, late colonial and immediate post-colonial and postcolonial times in South and South-East Asia. In doing so, this anthology addresses an important gap in the global understanding of documentary discourses, practices, uses and styles. Based upon in-depth essays written by international authorities in the field and cutting-edge doctoral projects, this anthology is the first to encompass different periods, national contexts, subject matter and style in order to address important and also relatively little-known issues in colonial documentary film in the South and South-East Asian regions. This anthology is divided into three main thematic sections, each of which crosses national or geographical boundaries. The first section addresses issues of colonialism, late colonialism and independence. The second section looks at the use of the documentary film by missionaries and Christian evangelists, whilst the third explores the relation between documentary film, nationalism and representation.

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