RESUMO
Similarly to other strict blood feeders, leeches from the Haementeria genus (Hirudinida: Glossiphoniidae) have established a symbiotic association with bacteria harbored intracellularly in esophageal bacteriomes. Previous genome sequence analyses of these endosymbionts revealed co-divergence with their hosts, a strong genome reduction, and a simplified metabolism largely dedicated to the production of B vitamins, which are nutrients lacking from a blood diet. 'Candidatus Providencia siddallii' has been identified as the obligate nutritional endosymbiont of a monophyletic clade of Mexican and South American Haementeria spp. However, the Haementeria genus includes a sister clade of congeners from Central and South America, where the presence or absence of the aforementioned symbiont taxon remains unknown. In this work, we report on a novel bacterial endosymbiont found in a representative from this Haementeria clade. We found that this symbiont lineage has evolved from within the Pluralibacter genus, known mainly from clinical but also environmental strains. Similarly to Ca. Providencia siddallii, the Haementeria-associated Pluralibacter symbiont displays clear signs of genome reduction, accompanied by an A+T-biased sequence composition. Genomic analysis of its metabolic potential revealed a retention of pathways related to B vitamin biosynthesis, supporting its role as a nutritional endosymbiont. Finally, comparative genomics of both Haementeria symbiont lineages suggests that an ancient Providencia symbiont was likely replaced by the novel Pluralibacter one, thus constituting the first reported case of nutritional symbiont replacement in a leech without morphological changes in the bacteriome. IMPORTANCE: Obligate symbiotic associations with a nutritional base have likely evolved more than once in strict blood-feeding leeches. Unlike those symbioses found in hematophagous arthropods, the nature, identity, and evolutionary history of these remains poorly studied. In this work, we further explored obligate nutritional associations between Haementeria leeches and their microbial symbionts, which led to the unexpected discovery of a novel symbiosis with a member of the Pluralibacter genus. When compared to Providencia siddallii, an obligate nutritional symbiont of other Haementeria leeches, this novel bacterial symbiont shows convergent retention of the metabolic pathways involved in B vitamin biosynthesis. Moreover, the genomic characteristics of this Pluralibacter symbiont suggest a more recent association than that of Pr. siddallii and Haementeria. We conclude that the once-thought stable associations between blood-feeding Glossiphoniidae and their symbionts (i.e., one bacteriome structure, one symbiont lineage) can break down, mirroring symbiont turnover observed in various arthropod lineages.
Assuntos
Sanguessugas , Filogenia , Simbiose , Animais , Sanguessugas/microbiologia , Sanguessugas/fisiologia , Genoma Bacteriano , Providencia/genética , Providencia/isolamento & purificação , Providencia/metabolismo , Providencia/classificação , Providencia/fisiologiaRESUMO
Providencia rettgeri, belonging to the genus Providencia, had gained significant interest due to its increasing prevalence as a common pathogen responsible for healthcare-associated infections in hospitals. P. rettgeri isolates producing carbapenemases have been reported to reduce the efficiency of carbapenems in clinical antimicrobial therapy. However, coexistence with other resistance determinants is rarely reported. The goal of this study was the molecular characterization of carbapenemase-producing Providencia spp. clinical isolates. Among 23 Providencia spp. resistant to imipenem, 21 were positive to blaNDM-1; one positive to blaNDM-1 and blaOXA-58 like; and one isolate co-producing blaIMP-27, blaOXA-24/40 like, and blaOXA-58 like were identified. We observed a low clonal relationship, and the incompatibility groups Col3M and ColRNAI were identified in the plasmid harboring blaNDM-1. We report for the first time a P. rettgeri strain co-producing blaIMP-27, blaOXA-24-like, and blaOXA-58 like. The analysis of these resistance mechanisms in carbapenemase co-producing clinical isolates reflects the increased resistance.
Assuntos
Antibacterianos , Providencia , Humanos , Antibacterianos/farmacologia , Providencia/genética , México/epidemiologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Proteínas de Bactérias/genéticaRESUMO
Providencia stuartii is one of the Enterobacteriaceae species of medical importance commonly associated with urinary infections, which can also cause other ones, including uncommon ones, such as liver abscess and septic vasculitis. This bacterium stands out in the expression of intrinsic and acquired resistance to antimicrobials. Besides, it uses mechanisms such as biofilm for its persistence in biotic and abiotic environments. This study investigated the cellular hydrophobicity profile of clinical isolates of P. stuartii. It also analyzed genes related to the fimbrial adhesin in this species comparing with other reports described for other bacteria from Enterobacteriaceae family. The investigated isolates to form biofilm and had a practically hydrophilic cell surface profile. However, fimH and mrkD genes were not found in P. stuartii, unlike observed in other species of Enterobacteriaceae. These results show that P. stuartii has specificities regarding its potential for biofilm formation, which makes it difficult to destabilize the infectious process and increases the permanence of this pathogen in hospital units.
Assuntos
Infecções por Enterobacteriaceae , Biofilmes , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/microbiologia , Humanos , Providencia/genéticaRESUMO
BACKGROUND: Providencia rettgeri is a nosocomial pathogen associated with urinary tract infections and related to Healthcare-Associated Infection (HAI). In recent years isolates producing New Delhi Metallo-ß-lactamase (NDM) and other ß-lactamases have been reported that reduce the efficiency of clinical antimicrobial treatments. In this study, we analyzed antibiotic resistance, the presence of resistance genes and the clonal relationship of two P. rettgeri isolates obtained from male patients admitted to the same hospital in Bogotá - Colombia, 2015. RESULTS: Antibiotic susceptibility profile evaluated by the Kirby-Bauer method revealed that both isolates were resistant to third-generation carbapenems and cephalosporins. Whole-genome sequencing (Illumina HiSeq) followed by SPAdes assembling, Prokka annotation in combination with an in-house Python program and resistance gene detection by ResFinder identified the same six ß-lactamase genes in both isolates: blaNDM-1, blaVIM-2, blaCTX-M-15, blaOXA-10, blaCMY-2 and blaTEM-1. Additionally, various resistance genes associated with antibiotic target alteration (arnA, PmrE, PmrF, LpxA, LpxC, gyrB, folP, murA, rpoB, rpsL, tet34) were found and four efflux pumps (RosAB, EmrD, mdtH and cmlA). The additional resistance to gentamicin in one of the two isolates could be explained by a detected SNP in CpxA (Cys191Arg) which is involved in the stress response of the bacterial envelope. Genome BLAST comparison using CGView, the ANI value (99.99%) and the pangenome (using Roary) phylogenetic tree (same clade, small distance) showed high similarity between the isolates. The rMLST analysis indicated that both isolates were typed as rST-61,696, same as the RB151 isolate previously isolated in Bucaramanga, Colombia, 2013, and the FDAARGOS_330 isolate isolated in the USA, 2015. CONCLUSIONS: We report the coexistence of the carbapenemase genes blaNDM-1, and blaVIM-2, together with the ß-lactamase genes blaCTX-M-15, blaOXA-10, blaCMY-2 and blaTEM-1, in P. rettgeri isolates from two patients in Colombia. Whole-genome sequence analysis indicated a circulation of P. rettgeri rST-61,696 strains in America that needs to be investigated further.
Assuntos
Proteínas de Bactérias/genética , Infecções por Enterobacteriaceae/microbiologia , Providencia/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Colômbia , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Providencia/efeitos dos fármacos , Providencia/isolamento & purificação , Resistência beta-Lactâmica/genéticaRESUMO
INTRODUCTION: In Colombia, between 2012 and 2013, 19 isolates with NDM were identified, of which 14 corresponded to Providencia rettgeri. METHODS: The isolates were identified by Vitek-2, and antimicrobial susceptibility was evaluated by broth microdilution. The carbapenemase phenotypes were determined with Modified Hodge Test and synergy tests with EDTA/SMA and APB, the genotypes by PCR using specific primers for KPC, GES, IMP, VIM, OXA-48 and NDM, and genetic relationships were established with DiversiLab. RESULTS: The isolates were resistant to carbapenems, third-generation cephalosporins, piperacillin-tazobactam, amikacin, gentamicin and tigecycline, except aztreonam. All isolates were positive for EDTA/SMA and NDM-1, and negative for APB and other carbapenemases. Two genetic groups, group 1 (n=9 isolates), group 2 (n=4 isolates) and an isolate defined as not genetically related. CONCLUSION: This work describes the circulating of NDM-1-producing P. rettgeri in Colombia.
Assuntos
Proteínas de Bactérias/análise , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/microbiologia , Providencia/isolamento & purificação , Resistência beta-Lactâmica , beta-Lactamases/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Colômbia/epidemiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Enterobacteriaceae/epidemiologia , Feminino , Genes Bacterianos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Providencia/efeitos dos fármacos , Providencia/enzimologia , Providencia/genética , Adulto Jovem , Resistência beta-Lactâmica/genética , beta-Lactamases/genéticaRESUMO
The emergence of multidrug-resistant Enterobacteriaceae strains producing carbapenemases, such as NDM-1, has become a major public health issue due to a high dissemination capacity and limited treatment options. Here we describe the draft genome of three NDM-1-producing isolates: Providencia rettgeri (CCBH11880), Enterobacter hormaechei subsp. oharae (CCBH10892) and Klebsiella pneumoniae (CCBH13327), isolated in Brazil. Besides blaNDM-1, resistance genes to aminoglycosides [aadA1, aadA2, aac(6')-Ib-cr] and quinolones (qnrA1, qnrB4) were observed which contributed to the multidrug resistance profile. The element ISAba125 was found associated to the blaNDM-1 gene in all strains.
Assuntos
Enterobacter/genética , Genoma Bacteriano/genética , Klebsiella pneumoniae/genética , Providencia/genética , beta-Lactamases/genética , Sequência de Bases , Brasil , Farmacorresistência Bacteriana/genética , Enterobacter/enzimologia , Humanos , Klebsiella pneumoniae/enzimologia , Dados de Sequência Molecular , Providencia/enzimologia , Análise de Sequência de DNARESUMO
CTX-M-131 is a natural Asp240Gly variant from the CTX-M-2 group detected in a Providencia rettgeri clinical strain from Brazil. Molecular analysis showed that blaCTX-M-131 was inserted in a complex class 1 integron harbored by a 112-kb plasmid, which has not been previously described as a platform for CTX-M-encoding genes with the Asp240Gly mutation. Steady-state kinetic parameters showed that the enzyme has a typical cefotaximase catalytic profile and an enhanced activity against ceftazidime.
Assuntos
Providencia/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Brasil , Ceftazidima/farmacologia , Integrinas/genética , Cinética , Plasmídeos/genética , beta-Lactamases/metabolismoRESUMO
A clinical Providencia stuartii isolate SM662 was recovered from a patient hospitalized in the intensive care unit at the Military hospital, Tunisia. This isolate was resistant to penicillins, cephalosporins, aminoglycosides and fluoroquinolones. A marked in vitro synergy between ceftazidime or cefotaxime and amoxicillin-clavulanic acid on Mueller-Hinton agar plates suggested the presence of an extended-spectrum-ß-lactamase. In addition, an unusual synergy was found between cefepime or aztreonam, and cefoxitin or imipenem on a double disk synergy test suggesting a VEB-type extended-spectrum-ß-lactamase. The characterization of ß-lactamases and associated resistance genes was performed by isoelectric focusing, polymerase chain reaction and nucleotide sequencing. Two ß-lactamases bands with pI values of 5.4 and 7.7, which were matched to TEM-1, VEB-1-a and OXA-2-like ß-lactamases were detected. The blaVEB-1-a gene was found to be associated with complex genetic structures, including Re elements. These ß-lactamases were not transferred by electroporation or conjugation experiments to the transconjugants and electroporants. Hybridization methods showed that the extended-spectrum-ß-lactamase encoding gene may have a chromosomal localization. The isolate SM662 produced the quinolone resistance determinants qnrA6 and aac(6')-Ib-cr which were successfully transferred. The detection of an associated chromosomal quinolone resistance revealed the presence of a gyrA mutation at codon 83 (Ser83Ile). This is the first report of the linkage VEB-1-a/OXA-2-like in P. stuartii associated with the description of qnrA6 and aac(6')-Ib-cr genes in this isolate.