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Microorganisms Jun 2023The current study aimed to evaluate the feasibility of using the aminoglycoside 2″-O-phosphotransferase gene as a positive selection marker in , , and . The gene,...
The current study aimed to evaluate the feasibility of using the aminoglycoside 2″-O-phosphotransferase gene as a positive selection marker in , , and . The gene, known to confer resistance to tobramycin, was PCR amplified from and cloned into two plasmid vectors, pMSG383 and pDB151, harboring hygromycin and zeocin selection markers, respectively. The recombinant plasmids were transformed into the target microorganisms, and selectability was assessed against varying concentrations of tobramycin and using an E-test against gentamicin. The results indicated that the gene is a useful selection marker in Mycobacteria and Nocardia against tobramycin, with a good selectability at 2.5-10 µg/mL for mc-155 and ATCC 19,247, and 60-160 µg/mL for ATCC 19,977 and H37Ra. The minimum inhibitory concentration (MIC) of gentamicin for recombinant , and was >256 µg/mL, whereas respective MIC in wild-type strains was 0.125 µg/mL, 0.38 µg/mL and 8 µg/mL, respectively. These findings demonstrate the potential of as a positive selection marker for genetic manipulation processes in Mycobacteria and Nocardia, thus facilitating their research and improving the efficiency of biotechnology applications. Conclusions: the gene is a useful, new selection marker for genetic manipulation of Nocardia and various Mycobacteria.
PubMed: 37512870
DOI: 10.3390/microorganisms11071697 -
Microorganisms Dec 2023The bacterial strain WB46 was isolated from the rhizosphere of willow plants ( L.) growing in soil contaminated with petroleum hydrocarbons. The strain was subjected to...
The bacterial strain WB46 was isolated from the rhizosphere of willow plants ( L.) growing in soil contaminated with petroleum hydrocarbons. The strain was subjected to whole-genome shotgun sequencing using Illumina HiSeq. Its draft genome is 7.15 Mb, with a 69.55% GC content, containing 6387 protein-coding genes and 51 tRNA and 15 rRNA sequences. The quality and reliability of the genome were assessed using CheckM, attaining an estimated genome completeness of 98.75% and an estimated contamination of 1.68%. These results indicate a high-quality genome (>95%) and low contamination (<5%). Many of these genes are responsible for petroleum hydrocarbon degradation, such as alkane 1-monooxygenase () and naphthalene dioxygenase (). 16S rRNA gene analysis, including in silico DNA-DNA hybridization (DDH) and average nucleotide identity (ANI), showed that strain WB46 belongs to the genus , and the most closely related species is The strain WB46 showed a distance of 63.4% and sequence identity of 88.63%, respectively. These values fall below the threshold levels of 70% and 95%, respectively, suggesting that the strain WB46 is a new species. We propose the name of sp. nov. for this new species. Interestingly, the sequence divergence of the 16S rRNA gene showed that the divergence only occurred in the V2 region. Therefore, the conventional V3-V4, V5-V7, or V8-V9 targeting metabarcoding, among others, would not be able to assess the diversity related to this new species.
PubMed: 38138115
DOI: 10.3390/microorganisms11122972 -
Monaldi Archives For Chest Disease =... Jun 2023Nocardiosis is an opportunistic infection that primarily targets the immunosuppressed. We investigate the differences in demographics and characteristics between...
Impact of immune status on the clinical characteristics, treatment outcomes and mortality of pulmonary nocardiosis: a retrospective analysis in a tertiary care hospital from a low to middle-income country.
Nocardiosis is an opportunistic infection that primarily targets the immunosuppressed. We investigate the differences in demographics and characteristics between immunosuppressed and immunocompetent patients with nocardiosis in a tertiary care hospital in Pakistan. Retrospective records were reviewed for patients diagnosed with pulmonary nocardiosis between 2010 and 2020. Immunosuppressed individuals were identified as those with autoimmune diseases, hematologic diseases and malignancies, HIV, immunosuppressant therapy, etc. Data collected included basic demographics, comorbid conditions, medication history, clinical presentation, radiological and microbiological data, and nocardiosis outcomes and complications. A total of 66 patients with nocardiosis were included in this study out of which 48 were immunosuppressed while 18 were immunocompetent. Both groups were compared for a number of variables including patient characteristics, underlying conditions, radiological findings, treatment regimen and outcomes. Immunosuppressed individuals were younger, and had higher rates of diabetes, chronic renal disease, chronic liver disease, higher platelet counts, surgical intervention, and longer hospital stays. Fever, dyspnea, and sputum production were the most common presentations. Nocardia asteroides was found to be the most common species of Nocardia overall. Nocardiosis presents differently in patients with immunosuppressed and immunocompetent patients consistent with previous studies. Nocardiosis should be considered in any patient presenting with treatment-resistant pulmonary or neurological symptoms.
PubMed: 37367100
DOI: 10.4081/monaldi.2023.2499 -
Cureus Apr 2024Nocardial mycetoma is a neglected tropical disease reported worldwide, especially in tropical and subtropical regions. It is ubiquitous in nature and is a soil-borne,...
Nocardial mycetoma is a neglected tropical disease reported worldwide, especially in tropical and subtropical regions. It is ubiquitous in nature and is a soil-borne, gram-positive, filamentous, aerobic bacteria with acute angle branching. Traumatic inoculation in endemic areas is the primary mode of infection of this debilitating disease. The clinical triad of tumefaction, draining sinus, and pus discharge with granules is very much characteristic and specific for clinching the diagnosis of mycetoma. However, the painless nature of the primary skin lesion often makes the patient present late to the clinician, often in the advanced stages of the disease. Here, we present a very intriguing case report of a young female patient who presented with a single neck nodule but was later diagnosed as a case of nocardial mycetoma. Timely diagnosis and initiation of therapy proved to be a boon for the patient with almost complete recovery within a few weeks in the form of healed skin lesions and insignificant scarring.
PubMed: 38716027
DOI: 10.7759/cureus.57753 -
Indian Dermatology Online Journal 2024
PubMed: 38282993
DOI: 10.4103/idoj.idoj_13_23