The Southern green stinkbug (N. viridula) feeds on developing soybean seeds in spite of their strong defenses against herbivory, making this pest one of the most harmful to soybean crops. To test the ...hypothesis that midgut bacterial community allows stinkbugs to tolerate chemical defenses of soybean developing seeds, we identified and characterized midgut microbiota of stinkbugs collected from soybean crops, different secondary plant hosts or insects at diapause on Eucalyptus trees. Our study demonstrated that while more than 54% of N. viridula adults collected in the field had no detectable bacteria in the V1-V3 midgut ventricles, the guts of the rest of stinkbugs were colonized by non-transient microbiota (NTM) and transient microbiota not present in stinkbugs at diapause. While transient microbiota Bacillus sp., Micrococcus sp., Streptomyces sp., Staphylococcus sp. and others had low abundance, NTM microbiota was represented by Yokenella sp., Pantoea sp. and Enterococcus sp. isolates. We found some isolates that showed in vitro β-glucosidase and raffinase activities plus the ability to degrade isoflavonoids and deactivate soybean protease inhibitors. Our results suggest that the stinkbugs´ NTM microbiota may impact on nutrition, detoxification and deactivation of chemical defenses, and Enterococcus sp., Yokenella sp. and Pantoea sp. strains might help stinkbugs to feed on soybean developing seeds in spite of its chemical defenses.
The spread of
arbapenem-resistant Enterobacterales has raised concern in clinical settings due to the limited therapeutic options available. OXA-48-like enzymes are still sporadic in South America. ...The aim of this study was to characterize a multidrug-resistant
isolate from a hospitalized patient in Buenos Aires city. The isolate was characterized phenotypically by determination of its susceptibility pattern, synergistic and colorimetric tests, and molecularly, by PCR, whole genome sequencing, and plasmid analysis. It belonged to ST-744, phylogroup A, and serotype O162/O89: H9. It remained susceptible to ceftazidime, meropenem, aminoglycosides, trimethoprim/sulfamethoxazole, and tigecycline. The presence of
harbored by a nonconjugative plasmid ColKp3, and
,
and
in 2 conjugative plasmids, together with their genetic environment, was revealed. To the best of our knowledge, this is the first report of the coproduction of the enzyme OXA-232 and the
gene in an
clinical isolate in South America in a patient who had not received colistin therapy.
Desulfovibrio spp. are strict anaerobes that are ubiquitous in nature. They can reside in the human or animal gastrointestinal tract and, as they are also environmental bacteria, may be present in ...soil and water. They can persist asymptomatically in the intestine or behave as opportunistic pathogens associated with primary bacteremia and intraabdominal infections. Several Desulfovibrio spp. infections may be underestimated due to their slow growth rate and because many laboratories do not routinely perform anaerobic cultures. Simple tests such as motility detection on a fresh subculture, Gram stain to confirm cell morphology, presence of H
S in SIM agar and production of a red fluorescence in alkaline pH under UV light would be indicative of Desulfovibrio spp. Here we report the case of Desulfovibrio desulfuricans bacteremia in a woman with clinical picture of abdominal sepsis due to gangrenous appendicitis with multiple organ failure.
Dolosigranulum pigrum in corneal abscess Roitman, Karina L; Almuzara, Marisa N; Fernández Rodriguez, Mario Javier ...
Revista argentina de microbiología,
04/2022
Journal Article
Recenzirano
Odprti dostop
Dolosigranulum pigrum is a gram-positive, facultatively anaerobic coccus, which is part of the oral and upper respiratory tract microbiota. Although reports of infections by this microorganism are ...scarce, it has been associated with a wide spectrum of infectious diseases. The case of an elderly man with a lower corneal abscess, in which Dolosigranulum pigrum was isolated, is described. The microorganism was identified by mass spectrometry (MALDI-TOF MS) and by the sequencing of the 16S rRNA gene. Furthermore, the presumptive identification of the causative agent was achieved by using key phenotypic tests such as the cluster arrangement in Gram stain, the negative catalase test, the production of pyrrolidonyl arylamidase and leucine aminopeptidase activity, the growth in 6.5% NaCl and esculin hydrolysis. The data from the literature (and the present case) support the association of the microorganism with ocular infections, which often take a destructive course, mainly in elderly patients.
The authors present a case report caused by Francisella novicida, a rare opportunistic human pathogen that may cause a tularemia-like disease in patients who are immunocompromised. The diagnosis is a ...challenge since it can be confused with Pasteurella or Brucella, and matrix-assisted laser desorption ionisation time-of-flight systems are limited due to its poor performance in identification.
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