Plasmid DNA in virulent and avirulent gonococci

The presence of covalently closed circular (CCC) DNA in virulent and avirulent colonial types of Neisseria gonorrhoeae strain 2686, and of type 3 colonies of strain F62 was investigated. CCC DNA was present in each, and the percentage of plasmid relative to total DNA was similar. The percentage of CCC DNA was similar in cells grown on a solid as compared with a liquid medium and in cells grown in the presence of varying concentrations of glucose. No correlation could be established between the presence of plasmid DNA and virulence of N. gonorrhoeae.

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Proteus mirabilis carrying NTEKPC-IId, blaNDM-1, blaOXA-10, aph(3')-VI, qnrD1 and IncQ and Col3M plasmids from a hospital in Recife-PE, Brazil

Research Society and Development ◽

10.33448/rsd-v10i15.22919 ◽

2021 ◽

Vol 10 (15) ◽

pp. e399101522919

Author(s):

Elizabeth Maria Bispo Beltrão ◽

Érica Maria Oliveira ◽

Crhisllane Rafaele dos Santos Vasconcelos Vasconcelos ◽

Antônio Mauro Rezende ◽

Ana Catarina de Souza Lopes

Keyword(s):

Septic Shock ◽

Resistance Genes ◽

Plasmid Dna ◽

Public Hospital ◽

Amplicon Sequencing ◽

Multiple Infections ◽

Clinical Aspects ◽

Study Objective ◽

Resistance Determinants ◽

Total Dna

The present study objective to characterize the clinical aspects of a patient infected with two strains of P. mirabilis and the presence of resistance determinants in the two isolates from a patient at a public hospital in Recife-PE, Brazil. The total DNA of the isolates was extracted and submitted to PCR and amplicon sequencing for the investigation of resistance genes, blaKPC, blaOXA-10, blaOXA-23, blaOXA-48, blaOXA-58, blaVIM, blaIMP, blaSPM, blaGES, blaNDM, qnrD and aac(6')-Ib). Isolate P21-A2 harbored the aac(6')-Ib, blaOXA-10 and qnrD genes. One of the isolates, P20-A2, was selected for plasmid DNA sequencing. The results showed that the patient developed multiple infections with various pathogens including two strains of P. mirabilis. The patient was hospitalized for 103 days, had septic shock of skin, abdominal, pulmonary and ulcer focus, and died. Isolate P20-A2 harbored the genes blaNDM, qnrD, aph(3')-VI, blaKPC and blaOXA-10, and plasmids IncQ and Col3M, together with NTEKPC-IId. To our knowledge, this is the first report of P. mirabilis harboring NTEKPC-IId. Although P. mirabilis is standing out as a cause of nosocomial infections and a resistant multidrug pathogen, this species is still neglected, the emergence of these P. mirabilis isolates harboring aforementioned resistance determinants and the plasmids IncQ and Col3M demonstrate the potential for dissemination of important resistance genes, mainly in the case of P. mirabilis.

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Clinical Neisseria gonorrhoeae isolate with a N. meningitidis porA gene and no prolyliminopeptidase activity, Sweden, 2011 – danger of false-negative genetic and culture diagnostic results

Eurosurveillance ◽

10.2807/ese.17.09.20102-en ◽

2012 ◽

Vol 17 (9) ◽

Author(s):

D Golparian ◽

E Johansson ◽

M Unemo

Keyword(s):

Neisseria Gonorrhoeae ◽

False Negative ◽

Gonorrhoeae Strain ◽

Negative Results ◽

False Negative Results ◽

Gonorrhoeae Isolate

We describe a Neisseria gonorrhoeae strain, found in Sweden in 2011, that harbours a N. meningitidis porA gene causing false-negative results in PCRs targeting the gonococcal porA pseudogene. Furthermore, the strain had no prolyliminopeptidase (PIP) activity that many commercial biochemical kits for species verification in culture rely on. Enhanced awareness of the spread of such strains and screening for them can be crucial.

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Mischkolonien auxotropher und Wildtypzellen nach Behandlung von Esdierichia coli-Zellen mit salpetriger Säure

Zeitschrift für Naturforschung B ◽

10.1515/znb-1963-0315 ◽

1963 ◽

Vol 18 (3) ◽

pp. 245-252 ◽

Cited By ~ 10

Author(s):

F. Kaudewitz ◽

K. Moebus ◽

H. Kneser

Keyword(s):

Experimental Evidence ◽

Nitrous Acid ◽

Single Cells ◽

The Other ◽

Mathematical Treatment ◽

E Coli ◽

Type 3 ◽

Good Agreement ◽

Hybrid Dna ◽

In Cells

Cells of E. coli incubated in nitrous acid give rise 1. to unchanged wildtype colonies, 2. to colonies composed of wildtype and auxotrophic cells and 3. to colonies consisting of auxotrophic cells only. The mixed colonies are considered to originate from single cells each of them harbouring hybrid DNA with one subunit, probably a sisterstrand, changed by deamination of a cytosine or adenine, the other one with unchanged wildtype composition. In cells producing type 3 colonies this wildtype strand is mutated lethally by a separate deamination of a cytosine or adenine. A mathematical treatment of this hypothesis leads to predictions which are in good agreement with experimental evidence. The data obtained are used for an estimation of the number of gene-loci of E. coli.

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