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Enterobacter cloacae and E. aerogenes have been increasingly reported as important opportunistic pathogens. In this study, a high prevalence of multi-drug resistant isolates from Brazil, harboring several β-lactamase encoding genes was found. Several virulence genes were observed in E. aerogenes, contrasting with the E. cloacae isolates which presented none., (Copyright © 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)

Objectives: Enterobacter cloacae has recently emerged as an important agent of nosocomial infections owing to the dissemination of extended-spectrum β-lactamases and carbapenemases in this species. In this context, a rise in the therapeutic use of aminoglycosides was noticed, followed by the accelerated development of resistance mechanisms. In this study, we report the draft genome sequence of a multidrug-resistant E. cloacae subsp. cloacae strain (Ec2) isolated from an active surveillance culture of a patient with Chagas disease., Methods: Whole-genome sequencing (WGS) was performed using a Nextera XT DNA library and NextSeq platform., Results: WGS analysis revealed the presence of 5527 coding genes, 62 RNA-encoding genes and 275 pseudogenes. Strain Ec2 belongs to sequence type 395 (ST395) and carries 22 transferable antibiotic resistance genes, comprising eight antimicrobial classes, including the rmtD2 gene conferring high-level aminoglycoside resistance., Conclusions: This draft genome can be used in comparative genomic analyses with different E. cloacae strains. In addition, it could help at elucidating epidemiological aspects regarding the dissemination of clinically relevant resistance genes., (Copyright © 2017. Published by Elsevier Ltd.)

Introduction: The rapid global spread of carbapenem-resistant Enterobacteriaceae (CRE) is a threat to the health system., Methods: We evaluated the antimicrobial susceptibility profiles of 70 CRE isolated in a tertiary hospital in Brazil between August and December 2015, and determined their resistance mechanisms., Results: The most prevalent microorganism was Klebsiella pneumoniae (95.7%); it showed high-level resistance to carbapenems (>98%), with sensitivity to colistin (91.4%) and amikacin (98.6%). The bla KPC gene was detected in 80% of the CRE isolates., Conclusions: Evaluation of bacterial resistance contributes to an appropriate treatment, and the reduction of morbimortality and dissemination of resistance.

Clonal genotypes resistant to fungal diseases are an important component of the cocoa production system in southeastern Bahia state (Brazil), so that technologies for faster production of stronger and healthier plantlets are highly desirable. In this study, the effects of inoculated bacterial endophytes isolated from healthy adult cacao plants on seedlings, and aspects related to inoculation methods, colonization patterns, and photosynthesis were investigated. Sequencing of 16S rRNA, hsp-60, and rpo-B genes placed the wild-type isolates within the species Enterobacter cloacae (isolates 341 and 344) and Bacillus subtilis (isolate 629). Spontaneous rifampicin-resistant (rif(R)) variants for 344 were also produced and tested. Endophytic application was either by immersion of surface sterilized seeds in bacterial suspensions or direct inoculation into soil, 20 days after planting non-inoculated seeds into pots. Results from in vitro recovery of inoculated isolates showed that the wild-type endophytes and rif(R) variants systemically colonized the entire cacao seedlings in 15-20 days, regardless of the inoculation method. Some endophytic treatments showed significant increases in seedlings' height, number of leaves, and dry matter. Inoculation methods affected the combined application of endophytes, which maintained the growth-promotion effects, but not in the same manner as in single applications. Interestingly, the 344-3.2 rif(R) variant showed improved performance in relation to both the wild type and another related variant. Photosynthetic rates and stomatal conductance increased significantly for some endophytic treatments, being partially associated with effects on growth and affected by the inoculation method. The results suggest that E. cloacae and B. subtilis endophytes from healthy adult plants (not transmitted by seeds) were able to promote vegetative growth on cacao seedlings. The development of products for large-scale use in seedlings/plantlets production systems was discussed.

The aim was to evaluate the presence of Staphylococcus spp., Enterobacteriaceae and Pseudomonadaceae in the oral cavities of HIV-positive patients. Forty-five individuals diagnosed as HIV-positive by ELISA and Western-blot, and under anti-retroviral therapy for at least 1 year, were included in the study. The control group constituted 45 systemically healthy individuals matched to the HIV patients to gender, age and oral conditions. Oral rinses were collected and isolates were identified by API system. Counts of microorganisms from HIV and control groups were compared statistically by a Mann-Whitney test (α=5%). The percentages of individuals positive for staphylococci were similar between the groups (p=0.764), whereas for Gram-negative rods, a higher percentage was observed amongst HIV-positive (p=0.001). There was no difference in Staphylococcus counts between HIV and control groups (p=0.1008). Counts were lower in the oral cavities of patients with low viral load (p=0.021), and no difference was observed in relation to CD4 counts (p=0.929). Staphylococcus aureus was the most frequently isolated species in HIV group, and Staphylococcus epidermidis was the prevalent species in the control group. Significantly higher numbers of enteric bacteria and pseudomonas were detected in the oral cavities of the HIV group than in the control (p=0.0001). Enterobacter cloacae was the most frequently isolated species in both groups. Counts of enteric bacteria and pseudomonas were significantly lower in patients with low CD4 counts (p=0.011); however, there was no difference relating to viral load. It may be concluded that HIV group showed greater species diversity and a higher prevalence of Enterobacteriaceae/Pseudomonadaceae., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Aims: To investigate the bacterial diversity, antimicrobial resistance patterns and types of beta-lactamase genes in Gram-negative bacteria isolated from a hospital sewage treatment plant., Methods and Results: Between July and December 2008, we collected samples from influent, clarifier tank effluent and chlorine contact tank effluent from a sewage treatment plant service of a hospital located in the city of Rio de Janeiro, Brazil. Of the 221 isolates identified, 40% were characterized as extended-spectrum beta-lactamase (ESBL) producers. Nonpathogenic micro-organisms and some pathogenic genera were quantified. The most common ESBL-producing isolates were Klebsiella pneumoniae, Enterobacter cloacae and Escherichia coli. The bla(TEM), bla(SHV) and bla(CTX-M) genes were detected in 82, 48 and 67% of bacterial isolates, respectively., Conclusions: Results showed that hospital wastewater treatment plant is not suitable systems for the removal of all antibiotic-resistant micro-organisms present in hospital wastewaters., Significance and Impact of the Study: This study provides evidence that bacteria resistant to multiple antibiotics and their resistance genes that are usually present in the hospital can reach the environment, even after the use of hospital wastewater treatment plants., (© 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.)

The integron content of Gram-negative strains implicated in three distinct episodes of suspected cross-infection among inpatients was investigated and compared with ribotyping. In the first episode, ribotyping identified a strain of Acinetobacter, isolated over a 3-month period, responsible for an outbreak associated with the use of mechanical ventilation in the intensive care unit (ICU). The second episode concerned simultaneous isolations of Pseudomonas aeruginosa and Serratia marcescens from 13 bronchoscopy patients. In these two episodes, results obtained by analysis of integron content and ribotyping were in agreement and correctly identified the epidemiologically related strains. In the third episode, isolates of Enterobacter cloacae were collected from patients in the neonatal ICU over a 3-month period. Although several isolates belonged to the same ribotype, cross-infection could not always be confirmed when the integron content was analysed. Integron detection can be considered a useful tool for studying molecular epidemiology in hospital environments, facilitating the quick detection of possible cross-infection cases, especially in critical wards such as the ICU.

In order to evaluate the resolving power of several typing methods to identify relatedness among Brazilian strains of Enterobacter cloacae, we selected twenty isolates from different patients on three wards of a University Hospital (Orthopedics, Nephrology, and Hematology). Traditional phenotyping methods applied to isolates included biotyping, antibiotic sensitivity, phage-typing, and O-serotyping. Plasmid profile analysis, ribotyping, and macrorestriction analysis by pulsed-field gel electrophoresis (PFGE) were used as genotyping methods. Sero- and phage-typing were not useful since the majority of isolates could not be subtyped by these methods. Biotyping, antibiogram and plasmid profile permitted us to classify the samples into different groups depending on the method used, and consequently were not reliable. Ribotyping and PFGE were significantly correlated with the clinical epidemiological analysis. PFGE did not type strains containing nonspecific DNase. Ribotyping was the most discriminative method for typing Brazilian isolates of E. cloacae.