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This study delves into the genomic features of 10 Vibrio strains collected from deep-sea hydrothermal vents in the Pacific Ocean, providing insights into their evolutionary history and ecological adaptations. Through sequencing and pan-genome analysis involving 141 Vibrio species, we found that deep-sea strains exhibit larger genomes with unique gene distributions, suggesting adaptation to the vent environment. The phylogenomic reconstruction of the investigated isolates revealed the presence of 2 main clades: The first is monophyletic, consisting exclusively of Vibrio alginolyticus, while the second forms a monophyletic clade comprising both Vibrio antiquarius and Vibrio diabolicus species, which were previously isolated from deep-sea vents. All strains carry virulence and antibiotic resistance genes related to those found in human pathogenic Vibrio species which may play a wider ecological role other than host infection in these environments. In addition, functional genomic analysis identified genes potentially related to deep-sea survival and stress response, alongside candidate genes encoding for novel antimicrobial agents. Ultimately, the pan-genome we generated represents a valuable resource for future studies investigating the taxonomy, evolution, and ecology of Vibrio species.
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Genoma Bacteriano , Fontes Hidrotermais , Filogenia , Vibrio , Vibrio/genética , Fontes Hidrotermais/microbiologia , Evolução Molecular , Adaptação Fisiológica/genética , Oceano PacíficoRESUMO
BACKGROUND: Helicobacter pylori strains show a high level of genotypic diversity and express several genes that contribute to their pathogenicity and resistance. In Mozambique, there is lack of information regarding its resistance pattern to antibiotics. In this study, we aimed to investigate the prevalence of H. pylori and its genotypic resistance to clarithromycin, metronidazole, and fluoroquinolones in Mozambican dyspeptic patients. Since appropriate eradication should be based on the local resistance rate, our data will guide clinicians in choosing the best drugs for the effective treatment of H. pylori-infected patients. METHODS: This is a cross-sectional descriptive study conducted between June 2017 and June 2020, in which 171 dyspeptic patients were recruited, and through upper gastrointestinal endoscopy, gastric biopsies were collected from those patients. Polymerase chain reaction was performed for the detection of H. pylori and its resistance mechanisms to clarithromycin (23S rRNA), metronidazole (rdxA), and fluoroquinolones (gyrA); mutations conferring resistance to these antibiotics were investigated by sequencing 23S rRNA, rdxA, and gyrA genes. RESULTS: Of the 171 samples tested, H. pylori was detected in 56.1% (96/171). The clarithromycin resistance rate was 10.4% (the responsible mutations were A2142G and A2143G), the metronidazole resistance rate was 55.2% (4 types of mutations responsible for metronidazole resistance were identified which include, D59N, R90K, H97T, and A118T. However, in many cases, they appeared in combination, with D59N + R90K + A118T being the most frequent combination), and the fluoroquinolones resistance rate was 20% (the responsible mutations were N87I and D91G). CONCLUSION: H. pylori infection remains common in dyspeptic Mozambican patients. High resistance to metronidazole and fluoroquinolones requires continuous monitoring of antibiotic resistance and adaptation of therapy to eradicate this infection.
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Infecções por Helicobacter , Helicobacter pylori , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Infecções por Helicobacter/epidemiologia , Moçambique , RNA Ribossômico 23S/genética , Estudos Transversais , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Rare information is available on clinical Enterococcus faecium encountered in Sardinia, Italy. This study investigated the antimicrobial susceptibility profiles and genotypic characteristics of E. faecium isolated at the University Hospital of Sassari, Italy, using the Vitek2 system and PCR, MLST, or WGS. Vitek2 revealed two VanB-type vancomycin-resistant Enterococcus faecium (VREfm) isolates (MICs mg/L = 8 and ≥32) but failed to detect vancomycin resistance in one isolate (MIC mg/L ≤ 1) despite positive genotypic confirmation of vanB gene, which proved to be vancomycin resistant by additional phenotypic methods (MICs mg/L = 8). This vanB isolate was able to increase its vancomycin MIC after exposure to vancomycin, unlike the "classic" occult vanB-carrying E. faecium, becoming detectable by Vitek 2 (MICs mg/L ≥ 32). All three E. faecium had highly mutated vanB2 operons, as part of a chromosomally integrated Tn1549 transposon, with common missense mutations in VanH and VanB2 resistance proteins and specific missense mutations in the VanW accessory protein. There were additional missense mutations in VanS, VanH, and VanB proteins in the vanB2-carrying VREfm isolates compared to Vitek2. The molecular typing revealed a polyclonal hospital-associated E. faecium population from Clade A1, and that vanB2-VREfm, and nearly half of vancomycin-susceptible E. faecium (VSEfm) analyzed, belonged to ST117. Based on core genome-MLST, ST117 strains had different clonal types (CT), excluding nosocomial transmission of specific CT. Detecting vanB2-carrying VREfm isolates by Vitek2 may be problematic, and alternative methods are needed to prevent therapeutic failure and spread.
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BACKGROUND: . Microbiological quality of drinking water supplied in Moamba, a small town in southern Mozambique, was assessed by collecting and analyzing 91 water sample from 5 sampling sites: raw or inlet water, treated water and 3 household taps along the water distribution system. The presence of Escherichia coli as indicator fecal contamination, three bacterial pathogens, Vibrio cholerae, Salmonella and Campylobacter spp., and Cefotaximee resistant E. coli as antibiotic resistance determinant, was assessed. RESULTS: . The results showed fecal contamination in all types of water samples: E. coli was found in 100% of inlet water samples, in 21% of treated water samples, and in 22% of tap water samples. No Salmonella spp. was detected during the study. The presence of V. cholerae was detected in 42% of all water samples tested: 100% of inlet water samples, in 16% of treated water samples, and in 23% household tap water samples. All V. cholerae confirmed isolates where genotyped by PCR as non-O1/non-O139; however, 9 isolates showed the presence of the genes encoding for cholera toxin. The presence of Campylobacter spp. was detected in 36% of the water samples tested: in 95% of inlet water samples, in 10% of treated water samples and in 23% household tap water samples. Cefotaxime resistant E. coli was detected in 63% of inlet water, 16% of treated water, and in 9% of tap water samples, these isolates were also resistant to multiple other antibiotics: ampicillin, streptomycin, tetracycline chloramphenicol. All 70 V. cholerae non-O1/non-O139 confirmed isolated were resistant to ampicillin, 51% to streptomycin, 13% to gentamycin, and 1 isolate was resistant to tetracycline; 13% showed a multi-drug resistant profile, being resistant to at least three antibiotics. CONCLUSION: . The presence of fecal contamination and pathogens in the water treatment system and household taps in Moamba indicates a health risk for the population. This burden increases by the presence of bacterial pathogens showing multidrug resistance.
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Cólera , Água Potável , Vibrio cholerae , Ampicilina , Antibacterianos/farmacologia , Cefotaxima , Cloranfenicol , Cólera/epidemiologia , Cólera/microbiologia , Toxina da Cólera/genética , Resistência Microbiana a Medicamentos , Escherichia coli/genética , Gentamicinas , Humanos , Moçambique , Estreptomicina , Tetraciclinas , Microbiologia da Água , Abastecimento de ÁguaRESUMO
Extended-spectrum ß-lactamase (ESBL)-producing extraintestinal pathogenic Escherichia coli (ExPEC), particularly high-risk lineages, are responsible for severe infections and increased mortality and hospital costs worldwide, with a major burden in low-income countries. Here we determined the antimicrobial susceptibility and performed whole-genome sequencing of E. coli isolates from extraintestinal infections of patients during 2017-2018 at Maputo Central Hospital (Mozambique). Multidrug resistance was displayed by 71% of isolates (17/24). All isolates resistant to cefotaxime and ceftazidime were positive for ESBL genes (16/24; 67%) and were co-resistant to amoxicillin/clavulanate (14/16; 88%), piperacillin/tazobactam (8/16; 50%), gentamicin (12/16; 75%), trimethoprim/sulfamethoxazole (15/16; 94%) and ciprofloxacin (11/16; 69%). Several major high-risk ExPEC lineages were identified, such as H30Rx-ST131, fimH41-ST131, H24Rx-ST410, ST617, ST361 and ST69 harbouring blaCTX-M-15, and H30R-ST131, ST38 and ST457 carrying blaCTX-M-27. Dissemination of CTX-M transposition units (ISEcp1-blaCTX-M-15-orf477 and ISEcp1-blaCTX-M-27-IS903B) among different sequence types could be occurring through the mobility of IncF plasmids. Additionally, all H24Rx-ST410 isolates carried ISEcp1-mediated blaCMY-2 AmpC and specific mutations in PBP3/OmpC proteins, potentially contributing to carbapenem resistance even in the absence of carbapenemase genes. Genome analysis highlighted a high assortment of ExPEC/UPEC virulence-associated genes mainly involved in adhesion, invasion, iron uptake and secretory systems among isolates, and an ExPEC/EAEC hybrid pathotype (fimH27-ST131_O18-ac:H4) showing the highest virulence gene content. cgMLST showed clonality and closely related isolates, particularly among ST131 and ST410, suggesting hospital-acquired infections and long-term ward persistence. Our study provides new insights into ExPEC clones, urging measures to prevent and contain their diffusion in this hospital and Mozambique.
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Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Extraintestinal Patogênica , Amoxicilina , Antibacterianos/farmacologia , Carbapenêmicos , Cefotaxima , Ceftazidima , Ciprofloxacina , Ácido Clavulânico , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Proteínas de Escherichia coli/genética , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli Extraintestinal Patogênica/metabolismo , Gentamicinas , Hospitais , Humanos , Ferro , Moçambique/epidemiologia , Piperacilina , Tazobactam , Combinação Trimetoprima e Sulfametoxazol , beta-Lactamases/genética , beta-Lactamases/metabolismoRESUMO
OBJECTIVES: Analyze the frequency of diarrheagenic Escherichia coli (DEC) pathotypes and their antimicrobial resistance profiles among children aged <15 years with diarrhea in four Mozambican provinces. METHODS: A cross-sectional hospital-based surveillance program of diarrhea was implemented in Maputo, Sofala, Zambézia, and Nampula. A single stool sample was collected from each child from May 2014 to May 2017. Culture methods and biochemical characterization were performed to detect E. coli strains. DEC pathotypes were determined by conventional polymerase chain reaction targeting specific virulence genes. Antimicrobial susceptibility was assessed by the Kirby-Bauer method. RESULTS: From 723 specimens analyzed by culture, 262 were positive for E. coli. A total of 208 samples were tested by polymerase chain reaction for DEC identification, of which 101 (48.6%) were positive for a DEC pathotype. The predominant pathotypes were enteroaggregative (66.3%, 67/101), enteropathogenic (15.8%, 16/101), enterotoxigenic (13.9%, 14/101), and enteroinvasive E. coli (4.0%, 4/101). No Shiga toxin-producing E. coli was identified. Regardless of the province, the most frequent pathotype was enteroaggregative E. coli. Isolated DEC presented high frequency of resistance to ampicillin (97.8%), tetracycline (68.3%), chloramphenicol (28.4%), nalidixic acid (19.5%), and gentamicin (14.4%). CONCLUSION: Children with diarrhea in Mozambique had DEC and higher resistance to ampicillin and tetracycline.
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Infecções por Escherichia coli , Escherichia coli , Ampicilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Criança , Estudos Transversais , Diarreia/tratamento farmacológico , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Moçambique/epidemiologia , TetraciclinaRESUMO
Microbial contamination of surface waters is of particular relevance in low-income and middle-income countries (LMICs) since they often represent the only available source of water for drinking and domestic use. In the recent years, a growing urbanization, profound demographic shifts and drastic climate events have greatly affected LMICs capacity to reach access to safe drinking water and sanitation practices, and to protect citizens' health from risks associated to the exposure and use of contaminated water. Detailed phylogenetic and microbiological information on the exact composition of pathogenic organisms in urban and peri-urban water is scarce, especially in rapidly changing settings of sub-Saharan Africa. In this review we aim to highlight how large-scale water pathobiome studies can support the LMICs challenge to global access to safe water and sanitation practices.
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Água Potável , Saneamento , Países em Desenvolvimento , Filogenia , Abastecimento de ÁguaRESUMO
Rickettsia africae is a bacterium of zoonotic importance, which causes African tick bite fever (ATBF) in humans. This pathogen is transmitted by ticks of the genus Amblyomma, with Amblyomma hebraeum and Amblyomma variegatum being the major vectors. Tick species other than the above-mentioned have also been reported to carry R. africae DNA. There is scarcity of information on the epidemiology of this pathogen, yet several cases have been recorded in foreign travellers who visited endemic areas, especially southern Africa. The disease has rarely been described in people from endemic regions. The aim of this study was to discuss the information that is currently available on the epidemiology of R. africae, highlighting the gaps in this field. Furthermore, ATBF cases, clinical signs and the locations where the cases occurred are also listed in this review.
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Interações Hospedeiro-Patógeno , Infecções por Rickettsia/epidemiologia , Amblyomma , Animais , Feminino , Saúde Global , Humanos , Masculino , Rickettsia/fisiologia , Infecções por Rickettsia/microbiologia , Doenças Transmitidas por CarrapatosRESUMO
Evolution of virulence traits from adaptation to environmental niches other than the host is probably a common feature of marine microbial pathogens, whose knowledge might be crucial to understand their emergence and pathogenetic potential. Here, we report genome sequence analysis of a novel marine bacterial species, Vibrio bathopelagicus sp. nov., isolated from warm bathypelagic waters (3309 m depth) of the Mediterranean Sea. Interestingly, V. bathopelagicus sp. nov. is closely related to coastal Vibrio strains pathogenic to marine bivalves. V. bathopelagicus sp. nov. genome encodes genes involved in environmental adaptation to the deep-sea but also in virulence, such as the R5.7 element, MARTX toxin cluster, Type VI secretion system and zinc-metalloprotease, previously associated with Vibrio infections in farmed oysters. The results of functional in vitro assays on immunocytes (haemocytes) of the Mediterranean mussel Mytilus galloprovincialis and the Pacific oyster Crassostrea gigas, and of the early larval development assay in Mytilus support strong toxicity of V. bathopelagicus sp. nov. towards bivalves. V. bathopelagicus sp. nov., isolated from a remote Mediterranean bathypelagic site, is an example of a planktonic marine bacterium with genotypic and phenotypic traits associated with animal pathogenicity, which might have played an evolutionary role in the origin of coastal marine pathogens.
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Crassostrea , Mytilus , Vibrioses , Vibrio , Animais , Mar Mediterrâneo , Vibrio/genéticaRESUMO
The development of carbapenem resistance in extraintestinal pathogenic Escherichia coli (ExPEC) has significant clinical implications, particularly in countries where second-line antimicrobials are not readily available, rendering treatments ineffective, and ExPEC infections untreatable. Thus, early detection of high-risk ExPEC lineages and raising awareness of the specific mechanisms underlying carbapenem resistance are mandatory for the selection of appropriate treatment options and the prevention of E. coli spread. This study aims to investigate the phenotypic and genotypic features of the first NDM-5 carbapenemase-producing ExPEC strain isolated from the blood of a patient admitted to the Maputo Central Hospital (MCH), in Mozambique. E. coli SSM100 isolate was identified by MALDI-TOF, it displayed high-level resistance to third generation cephalosporins, carbapenems, fluoroquinolones, and aminoglycosides, performing antimicrobial susceptibilities testing by VITEK 2 system. E. coli SSM100 isolate was classified through whole-genome sequencing as ST405-D-O102: H6, a globally distributed lineage associated with antimicrobial resistance, carrying the blaNDM-5 gene located on an F1:A1:B49 plasmid, coharboring blaCTX-M-15, blaTEM-1, aadA2, sul1, and dfrA12 genes. In addition, mutations in gyrA (S83L and D87N), parC (S80I and E84V), and parE (I529L) conferring fluoroquinolone resistance were also found. Moreover, SSM100 isolate carried 88 virulence genes, of which 28 are reported to be associated with UPEC. The emergence of NDM-5 carbapenemase in a pandemic ST405-D-O102:H6 clone in Mozambique is of great concern. Locations of extended-spectrum ß-lactamase determinants and NDM-5 carbapenemase gene on IncF-plasmid can increase their spread reinforcing the need for antimicrobial surveillance and the urgent introduction of carbapenemase detection tests in diagnostic laboratories of the country.
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Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli Extraintestinal Patogênica/efeitos dos fármacos , Escherichia coli Extraintestinal Patogênica/crescimento & desenvolvimento , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli Extraintestinal Patogênica/isolamento & purificação , Genes Bacterianos , Genótipo , Testes de Sensibilidade Microbiana , Moçambique , Fenótipo , Plasmídeos , Virulência , Sequenciamento Completo do Genoma , beta-Lactamases/genéticaRESUMO
This study reports a genomic analysis of Escherichia coli isolates recovered from 25 bovine fecal composite samples collected from four different production units in Maputo city and around Maputo Province, Mozambique. The genomes were analyzed to determine the presence of antibiotic resistance genes (ARGs), genetic relatedness, and virulence factors known to cause diseases in humans. Whole-genome sequencing was conducted on 28 isolates using an Illumina NextSeq 500 sequencing platform. The genomes were analyzed using BLASTN for the presence of resistance genes and virulence factors, as well as to determine their phylogenetic groups, sequence types (ST), and ST complexes (ST Cplxs). The majority of the isolates (85%) were identified as members of phylogenetic groups B1, with fewer isolates identified as members of group A, and a single isolate identified as group "E/Clade I." The ST analysis demonstrated a higher level of diversity than the phylogenetic group analysis. Sixteen different STs, five ST Cplxs, and seven singleton complexes were identified. A strain identified as a novel ST (ST9215) showed a high level of similarity with an isolate recovered from a wild animal in the Gambia. Seven different ARGs were identified, with tet(B) being the most frequently detected, followed by aph(3â³)-Ib, aph(6)-Id, sul2, blaTEM-1B, and dfrA1. Three isolates encoded ß-lactam-conferring point mutations in the ampC promoter (-42C>T). In total, 51 different virulence factors were identified among the genomes. This study demonstrates that E. coli from bovine sources in Mozambique encoded multiple antibiotic resistance elements, plasmids, and virulence factors. To the best of our knowledge, this is the first genomic description of antibiotic-resistant E. coli isolated from bovine sources in Mozambique.
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Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Microbiologia de Alimentos/estatística & dados numéricos , Genoma Bacteriano/genética , Fatores de Virulência/genética , Animais , Antibacterianos/farmacologia , Bovinos , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Testes de Sensibilidade Microbiana , Moçambique , Filogenia , Plasmídeos/genética , Sequenciamento Completo do GenomaRESUMO
The significance of large tropical lakes as environmental reservoirs of Vibrio cholerae in cholera endemic countries has yet to be established. By combining large scale plankton sampling, microbial culture and ultrasensitive molecular methods, namely Droplet Digital PCR (ddPCR) and targeted genomics, the presence of Vibrio cholerae was investigated in a 96,600 L volume of surface water collected on a 322 nautical mile (596 km) transect in Lake Tanganyika. V. cholerae was detected and identified in a large area of the lake. In contrast, toxigenic strains of V. cholerae O1 or O139 were not detected in plankton samples possibly in relation to environmental conditions of the lake ecosystem, namely very low salinity compared to marine brackish and coastal environments. This represents to our knowledge, the largest environmental study to determine the role of tropical lakes as a reservoir of V. cholerae.
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INTRODUCTION: Rickettsia are Gram-negative and obligate intracellular bacteria, which cause typhus and spotted fever-like diseases in humans. In Africa, Rickettsia africae of the Spotted Fever Group Rickettsia (SFGR) is the etiologic agent of the African Tick-Bite Fever. The disease is transmitted by ticks of the genus Amblyomma, which serve as vectors and reservoirs of Rickettsia. In this study, we aimed to detect Rickettsia species in ticks collected from cattle in south and central Mozambique. METHODOLOGY: DNA from 412 adult ticks and 22 pools of larvae were extracted and tested for the presence of Rickettsia genes gltA, ompA and ompB by PCR, followed by sequencing and phylogenetic analysis. RESULTS: Our results showed that in adult ticks, 79.5% (n = 330), 66% (n = 274) and 67% (n = 275) samples were positive for gltA, ompA and ompB genes, respectively. Among the 22 pools of larvae analysed, 77.2% (n = 17) were positive for the three genes tested. The infection rates ranged from 43% to 100% for Rickettsia by gltA in all locations studied, with maximum values of 100% observed in the districts of Maputo province namely Changalane, Boane and Matutuine district. The phylogenetic analysis of amplified sequences revealed that samples under study grouped with R. africae for the 3 genes. CONCLUSION: The study showed that Spotted Fever Group Rickettsia represented by R. africae widely circulate in Amblyomma ticks collected in south and central regions of Mozambique.
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Amblyomma/microbiologia , Genes Bacterianos/genética , Filogenia , Infecções por Rickettsia/veterinária , Rickettsia/genética , Animais , Bovinos/parasitologia , DNA Bacteriano/genética , Moçambique , Rickettsia/classificação , Análise de Sequência de DNARESUMO
Enterococcus faecium has become a globally disseminated nosocomial pathogen mainly because of acquisition and diffusion of virulence factors and multidrug resistance determinants, including glycopeptides, which are some of the last resort antimicrobials used to treat more serious infections common in high-risk patients. In this study we investigated and characterized hospital-associated (HA) E. faecium isolates collected at Hue Central Hospital, Vietnam. Our results highlighted the spread among hospital wards of a surprisingly heterogeneous multidrug-resistant E. faecium population comprising five different CC17-related sequence types (STs), of which 46% VREf carry the vanB gene. Whole genome sequencing of selected E. faecium isolates showed that VREf from different STs carried the same chromosomal integrated Tn1549-like transposon, with a highly mutated vanB2-operon, showing an increased level of vancomycin resistance (VanB phenotype) and able, in one isolate, to confer resistance to teicoplanin (VanA incongruent phenotype). Two unusual vanA/vanB2-type strains were detected within the vanB2-type ST17 population, harbouring a Tn1546-vanA-like transposon in pJEG40-like plasmids. Wg-SNPs-based analysis showed the genetic relatedness of VSEf/VREf of the same STs and indicated lateral exchange of the Tn1549-like element among isolates followed by clonal expansion. Microevolution among ST17 isolates, including the vanA/vanB2-type strains, and inter-wards VREf transmission, were highlighted. The use of teicoplanin is strongly discouraged in the study hospital because of the spreading of Tn1549-vanB2 associated to teicoplanin resistance. A rational use of glycopeptides and effective surveillance measures are required to reduce nosocomial VSEF/VREf spread and to avoid the rise of unusual and misleading VREf genotypes.
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Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Enterococcus faecium/isolamento & purificação , Genótipo , Enterococos Resistentes à Vancomicina/isolamento & purificação , Cromossomos Bacterianos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , Elementos de DNA Transponíveis , Transmissão de Doença Infecciosa , Farmacorresistência Bacteriana , Enterococcus faecium/genética , Evolução Molecular , Transferência Genética Horizontal , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/transmissão , Hospitais , Humanos , Epidemiologia Molecular , Tipagem Molecular , Mutação , Óperon , Plasmídeos , Polimorfismo de Nucleotídeo Único , Teicoplanina/farmacologia , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/genética , Vietnã/epidemiologia , Sequenciamento Completo do GenomaRESUMO
Vibrio parahaemolyticus is the leading cause of bacterial gastroenteritis associated with seafood consumption in the United States. Here we investigated the presence of virulence factors and genetic diversity of V. parahaemolyticus isolated from water, oyster, and sediment samples from the Chesapeake Bay, Maryland. Of more than 2,350 presumptive Vibrio collected, more than half were confirmed through PCR as V. parahaemolyticus, with 10 encoding both tdh and trh and 6 encoding only trh. Potentially pathogenic V. parahaemolyticus were then serotyped with O1:KUT and O3:KUT predominant. Furthermore, pulsed-field gel electrophoresis was performed and the constructed dendrogram displayed high diversity, as did results from multiple-locus VNTR analysis. Vibrio parahaemolyticus was readily isolated from Chesapeake Bay waters but was less frequently isolated from oyster and sediment samples collected during this study. Potentially pathogenic V. parahaemolyticus was isolated in fewer numbers and the isolates displayed expansive diversity. Although characteristics of the pathogenic V. parahaemolyticus were highly variable and the percent of pathogenic V. parahaemolyticus detected was low, it is important to note that, pathogenic V. parahaemolyticus are present in the Chesapeake Bay, warranting seafood monitoring to minimize risk of disease for the public, and to reduce the economic burden of V. parahaemolyticus related illness.
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Enterococcus faecium/classificação , Enterococcus faecium/genética , Variação Genética , Genótipo , Tipagem de Sequências Multilocus/métodos , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Enterococcus faecium/isolamento & purificação , Genoma Bacteriano , Infecções por Bactérias Gram-Positivas/microbiologia , Hospitais , Humanos , Epidemiologia Molecular/métodos , Arábia Saudita , Enterococos Resistentes à Vancomicina/isolamento & purificaçãoRESUMO
INTRODUCTION: Africa is increasingly affected by cholera. In Mozambique, cholera appeared in the early 1970s when the seventh pandemic entered Africa from the Indian subcontinent. In the following decades, several epidemics were registered in the country, the 1997-1999 epidemic being the most extended. Since then, Mozambique has been considered an endemic area for cholera, characterized by yearly outbreaks occurring with a seasonal pattern. At least three pandemic variants are thought to have originated in the Indian subcontinent and spread worldwide at different times. To understand the epidemiology of cholera in Mozambique, whether the disease re-emerges periodically or is imported by different routes of transmission, we investigated clinical V. cholerae O1 isolated during 1997-1999 and 2012-2014 epidemics. METHODOLOGY: By detecting and characterizing seven genetic elements, the mobilome profile of each isolate was obtained. By comparing it to known seventh pandemic reference strains, it was possible to discern among different V. cholerae O1 variants active in the country. RESULTS: During 1997-1999, epidemic strains showed two different genetic profiles, both related to a pandemic clone that originated from India and was reported in other African countries in the 1990s. Isolates from 2012-2014 outbreaks showed a genetic background related to the pandemic strains currently active as the prevalent causative agent of cholera worldwide. CONCLUSIONS: Despite cholera being endemic in Mozambique, the epidemiology of the disease in the past 20 years has been strongly influenced by the cholera seventh pandemic waves that originated in the Indian subcontinent.
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Cólera/epidemiologia , Epidemias , Genótipo , Vibrio cholerae/classificação , Vibrio cholerae/genética , Cólera/transmissão , Transmissão de Doença Infecciosa , Humanos , Epidemiologia Molecular , Moçambique/epidemiologia , Vibrio cholerae/isolamento & purificaçãoRESUMO
INTRODUCTION: Diarrheagenic Escherichia coli (DEC) represents one of the leading cause of diarrhoea in developing countries. In this study a molecular approach was applied for the detection of diarrheagenic Escherichia coli (DEC) circulating in Maputo, Mozambique. METHODOLOGY: All isolates were PCR tested for species-specific genes and for 11 molecular markers: stx1, stx2, eae, bfpA, lt, st, ipaH, aap, aggR CVD432 and daaE. RESULTS: Of the 80 E. coli isolated, 74% were potential DEC: 21% EIEC, 19% EPEC, 15% EAEC, 13% ETEC, 5% DAEC and 1% hybrids. CONCLISION: This study revealed the complexity of the etiology of diarrhea caused by pathogenic E. coli in Mozambique, and the risk of the emergence of new pathogenic variants due to the horizontal transmission of pathogenicity factors.
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Diarreia/microbiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Genes Bacterianos , Fatores de Virulência/genética , Criança , Pré-Escolar , Diarreia/epidemiologia , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Transferência Genética Horizontal , Variação Genética , Genótipo , Humanos , Lactente , Moçambique/epidemiologia , Reação em Cadeia da PolimeraseRESUMO
Vibrio species are both ubiquitous and abundant in marine coastal waters, estuaries, ocean sediment, and aquaculture settings worldwide. We report here the isolation, characterization, and genome sequence of a novel Vibrio species, Vibrio antiquarius, isolated from a mesophilic bacterial community associated with hydrothermal vents located along the East Pacific Rise, near the southwest coast of Mexico. Genomic and phenotypic analysis revealed V. antiquarius is closely related to pathogenic Vibrio species, namely Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio harveyi, and Vibrio vulnificus, but sufficiently divergent to warrant a separate species status. The V. antiquarius genome encodes genes and operons with ecological functions relevant to the environment conditions of the deep sea and also harbors factors known to be involved in human disease caused by freshwater, coastal, and brackish water vibrios. The presence of virulence factors in this deep-sea Vibrio species suggests a far more fundamental role of these factors for their bacterial host. Comparative genomics revealed a variety of genomic events that may have provided an important driving force in V. antiquarius evolution, facilitating response to environmental conditions of the deep sea.
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Fontes Hidrotermais/microbiologia , Vibrio/isolamento & purificação , Vibrio/patogenicidade , Evolução Molecular , Genoma Bacteriano , Humanos , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Especificidade da Espécie , Vibrio/genética , Virulência/genéticaRESUMO
UNLABELLED: SXT-R391 Integrative conjugative elements (ICEs) are self-transmissible mobile genetic elements able to confer multidrug resistance and other adaptive features to bacterial hosts, including Vibrio cholerae, the causative agent of cholera. ICEs are arranged in a mosaic genetic structure composed of a conserved backbone interspersed with variable DNA clusters located in conserved hot spots. In this study, we investigated ICE acquisition and subsequent microevolution in pandemic V. cholerae. Ninety-six ICEs were retrieved from publicly available sequence databases from V. cholerae clinical strains and were compared to a set of reference ICEs. Comparative genomics highlighted the existence of five main ICE groups with a distinct genetic makeup, exemplified by ICEVchInd5, ICEVchMoz10, SXT, ICEVchInd6, and ICEVchBan11. ICEVchInd5 (the most frequent element, represented by 70 of 96 elements analyzed) displayed no sequence rearrangements and was characterized by 46 single nucleotide polymorphisms (SNPs). SNP analysis revealed that recent inter-ICE homologous recombination between ICEVchInd5 and other ICEs circulating in gammaproteobacteria generated ICEVchMoz10, ICEVchInd6, and ICEVchBan11. Bayesian phylogenetic analyses indicated that ICEVchInd5 and SXT were independently acquired by the current pandemic V. cholerae O1 and O139 lineages, respectively, within a period of only a few years. IMPORTANCE: SXT-R391 ICEs have been recognized as key vectors of antibiotic resistance in the seventh-pandemic lineage of V. cholerae, which remains a major cause of mortality and morbidity on a global scale. ICEs were acquired only recently in this clade and are acknowledged to be major contributors to horizontal gene transfer and the acquisition of new traits in bacterial species. We have reconstructed the temporal dynamics of SXT-R391 ICE acquisition and spread and have identified subsequent recombination events generating significant diversity in ICEs currently circulating among V. cholerae clinical strains. Our results showed that acquisition of SXT-R391 ICEs provided the V. cholerae seventh-pandemic lineage not only with a multidrug resistance phenotype but also with a powerful molecular tool for rapidly accessing the pan-genome of a large number of gammaproteobacteria.