Molecular characterization of a mitochondrial mutant carrying point mutations in the 3′ untranslated region of theCOX3mRNA fromSaccharomyces cerevisiae

SummaryCongenital afibrinogenemia (CAF) is a rare coagulation disorder characterized by very low or unmeasurable levels of functional and immunoreactive fibrinogen in plasma, associated with a hemorrhagic phenotype of variable severity. It is transmitted as an autosomal recessive trait (prevalence 1:1,000,000) and is invariantly associated with mutations affecting one of the three fibrinogen genes (FGA, FGB, and FGG, coding for Aα, Bβ, and γ chain, respectively). Fibrinogen is secreted by hepatocytes as a hexamer composed of two copies of each chain; the lack of one chain has been demonstrated to prevent its secretion. Most genetic defects causing afibrinogenemia are point mutations, where- as only three large deletions have been identified so far, all affecting the FGA gene. We here report the molecular characterization of six unrelated afibrinogenemic patients leading to the identification of eight different mutations, four hitherto unknown: a 4.1-Kb large deletion involving exon 1 of FGA (AC107385:g. 65682_69828del), two nonsense mutations (p.Trp229X in FGA and p.Trp266X in FGB), and an ins-del mutation (g.1787_ 1789del3ins12) in FGA. The molecular characterization of CAFcausing genetic defects increases our understanding on the genetic basis of this disease and might be helpful for prenatal screening purposes, as also demonstrated during this study.

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Epidemic and molecular characterization of fluoroquinolone-resistant Shigella dysenteriae 1 isolates from calves with diarrhea

BMC Microbiology ◽

10.1186/s12866-020-02050-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mingze Cao ◽

Weiwei Wang ◽

Liwei Zhang ◽

Guanhui Liu ◽

Xuzheng Zhou ◽

...

Keyword(s):

Molecular Characterization ◽

Virulence Genes ◽

Point Mutations ◽

Multidrug Resistant ◽

Gansu Province ◽

Quinolone Resistance ◽

Shigella Dysenteriae ◽

Fluoroquinolone Resistance ◽

And Control

Abstract Background The widespread distribution of antimicrobial-resistant Shigella has become a recurrent challenge in many parts of the developing world. Previous studies indicate that the host of Shigella has expanded from humans to animals. This study aimed to investigate the prevalence of fluoroquinolone resistance and associated molecular characterization of S. dysenteriae 1 isolated from calves. Results All 38 unduplicated S. dysenteriae 1 isolates were collected from calves in Gansu Province from October 2014 to December 2016. According to MLST and PFGE analysis, these isolates were separated into 4 and 28 genotypes, respectively. The most common STs identified were ST228 (34.21%, 13/38) and ST229 (39.47%, 15/38), which were first found in the present study. All isolates harbored virulence genes, and the incidence of the seven virulence genes were ipaH (100%), ipaBCD (92.11%), stx (73.68%), ial (57.89%), sen (28.95%), set1A and set1B (0%). According to the results of antimicrobial susceptibilities, 76.32% (29/38) were resistant to fluoroquinolone and showed multidrug resistance. In a study on the polymorphism of quinolone resistance–determining region (QRDR) of gyrA/B and parC/E genes, we identified two mutations in gyrA (Ser83 → Leu and Asp87 → Asn) and parC (Ser80 → Ile and Ser83 → Leu), respectively. Among them, 55.17% (16/29) of resistant strains had the gyrA point mutations (Ser83 → Leu) and parC point mutation (Ser83 → Leu). Moreover, 41.38% (12/29) of isolates had all five point mutations of gyrA and parC. In addition, the prevalence of the plasmid-mediated quinolone resistance (PMQR) determinant genes was also investigated. All 29 fluoroquinolone-resistant isolates were positive for the aac (6′)-Ib-cr gene but negative for qepA, except for SD001. In addition, only 6 (20.69%, 6/29) isolates harbored the qnr gene, including two with qnrB (6.90%, 2/29) and four with qnrS (13.79%, 4/29). Conclusion Given the increased common emergence of multidrug resistant isolates, uninterrupted surveillance will be necessary to understand the actual epidemic burden and control this infection.

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Epidemic and molecular characterization of fluoroquinolone-resistant Shigella dysenteriae 1 isolates from calves with diarrhea

10.21203/rs.3.rs-39629/v4 ◽

2020 ◽

Author(s):

Mingze Cao ◽

Weiwei Wang ◽

Liwei Zhang ◽

Guanhui Liu ◽

Xuzheng Zhou ◽

...

Keyword(s):

Molecular Characterization ◽

Virulence Genes ◽

Point Mutations ◽

Multidrug Resistant ◽

Gansu Province ◽

Quinolone Resistance ◽

Shigella Dysenteriae ◽

Fluoroquinolone Resistance ◽

And Control

Abstract Background: The widespread distribution of antimicrobial-resistant Shigella has become a recurrent challenge in many parts of the developing world. Previous studies indicate that the host of Shigella has expanded from humans to animals. This study aimed to investigate the prevalence of fluoroquinolone resistance and associated molecular characterization of S. dysenteriae 1 isolated from calves. Results: All 38 unduplicated S. dysenteriae 1 isolates were collected from calves in Gansu Province from October 2014 to December 2016. According to MLST and PFGE analysis, these isolates were separated into 4 and 28 genotypes, respectively. The most common STs identified were ST228 (34.21%, 13/38) and ST229 (39.47%, 15/38), which were first found in the present study. All isolates harbored virulence genes, and the incidence of the seven virulence genes were ipaH (100%), ipaBCD (92.11%), stx (73.68%), ial (57.89%), sen (28.95%), set1A and set1B (0%). According to the results of antimicrobial susceptibilities, 76.32% (29/38) were resistant to fluoroquinolone and showed multidrug resistance. In a study on the polymorphism of quinolone resistance–determining region (QRDR) of gyrA/B and parC/E genes, we identified two mutations in gyrA (Ser83→Leu and Asp87→Asn) and parC (Ser80→Ile and Ser83→Leu), respectively. Among them, 55.17% (16/29) of resistant strains had the gyrA point mutations (Ser83→Leu) and parC point mutation (Ser83→Leu). Moreover, 41.38% (12/29) of isolates had all five point mutations of gyrA and parC. In addition, the prevalence of the plasmid-mediated quinolone resistance (PMQR) determinant genes was also investigated. All 29 fluoroquinolone-resistant isolates were positive for the aac(6’)-Ib-cr gene but negative for qepA, except for SD001. In addition, only 6 (20.69%, 6/29) isolates harbored the qnr gene, including two with qnrB (6.90%, 2/29) and four with qnrS (13.79%, 4/29). Conclusion: Given the increased common emergence of multidrug resistant isolates, uninterrupted surveillance will be necessary to understand the actual epidemic burden and control this infection.

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Clinical and Molecular Characterization of PMP22 point mutations in Taiwanese patients with Inherited Neuropathy

Scientific Reports ◽

10.1038/s41598-017-14771-5 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 4

Author(s):

Yi-Chu Liao ◽

Pei-Chien Tsai ◽

Thy-Sheng Lin ◽

Cheng-Tsung Hsiao ◽

Nai-Chen Chao ◽

...

Keyword(s):

Molecular Characterization ◽

Point Mutations ◽

Inherited Neuropathy

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Rifampicin-resistant meningococci causing invasive disease: detection of point mutations in the rpoB gene and molecular characterization of the strains

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/47.2.219 ◽

2001 ◽

Vol 47 (2) ◽

pp. 219-222 ◽

Cited By ~ 30

Author(s):

P. Stefanelli

Keyword(s):

Molecular Characterization ◽

Point Mutations ◽

Rpob Gene ◽

Invasive Disease ◽

Disease Detection

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Epidemic and molecular characterization of fluoroquinolone-resistant Shigella dysenteriae 1 isolates from calves with diarrhea

10.21203/rs.3.rs-32990/v1 ◽

2020 ◽

Author(s):

Zhen Zhu ◽

Mingze Cao ◽

Weiwei Wang ◽

Liwei Zhang ◽

Guanhui Liu ◽

...

Keyword(s):

Molecular Characterization ◽

Virulence Genes ◽

Point Mutations ◽

Multidrug Resistant ◽

Gansu Province ◽

Shigella Dysenteriae ◽

Fluoroquinolone Resistance ◽

Resistant Strains ◽

And Control

Abstract Background: The widespread distribution of antimicrobial-resistant Shigella has become a recurrent challenge in many parts of the developing world. Previous studies indicate that the host of Shigella has expanded from humans to animals. This study aimed to investigate the prevalence of fluoroquinolone resistance and associated molecular characterization of S. dysenteriae 1 isolated from calves. Methods and Results: All 38 unduplicated S. dysenteriae 1 isolates were collected from calves in Gansu Province from October 2014 to December 2016. According to MLST and PFGE analysis, these isolates were separated into 4 and 28 genotypes, respectively. The most common STs identified were ST228 (34.21%, 13/38) and ST229 (39.47%, 15/38), which were first found in the present study. All isolates harbored virulence genes, and the incidence of the five virulence genes were ipaH (100%), ipaBCD (92.11%), stx (73.68%), ial (57.89%), and sen (28.95%). According to the results of antimicrobial susceptibilities, 76.32% (29/38) of S. dysenteriae isolates were resistant to fluoroquinolone and showed multidrug resistance. In a study on the polymorphism of QRDR of gyrA/B and parC/E genes, we identified two mutations in gyrA (Ser83→Leu and Asp87→Asn) and parC (Ser80→Ile and Ser83→Leu), respectively. Among them, 55.17% (16/29) of resistant strains had the gyrA point mutations (Ser83→Leu) and parC point mutation (Ser83→Leu). Moreover, 41.38% (12/29) of isolates had all five point mutations of gyrA and parC. In addition, the prevalence of the PMQR determinant genes was also investigated. All 29 fluoroquinolone-resistant isolates were positive for the aac(6’)-Ib-cr gene but negative for qepA, except SD001. In addition, only 6 (20.69%, 6/29) isolates harbored the qnr gene, including two with qnrB (6.90%, 2/29) and four with qnrS (13.79%, 4/29). Conclusion: Given the increased common emergence of multidrug resistant isolates, uninterrupted surveillance will be necessary to understand the actual epidemic burden and control this infection.

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Characterization of a Lineage C.36 SARS-CoV-2 Isolate with Reduced Susceptibility to Neutralization Circulating in Lombardy, Italy

Viruses ◽

10.3390/v13081514 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1514

Author(s):

Matteo Castelli ◽

Andreina Baj ◽

Elena Criscuolo ◽

Roberto Ferrarese ◽

Roberta A. Diotti ◽

...

Keyword(s):

Molecular Characterization ◽

Single Point ◽

Point Mutations ◽

Humoral Response ◽

Genomic Sequencing ◽

Single Point Mutations

SARS-CoV-2 spike is evolving to maximize transmissibility and evade the humoral response. The massive genomic sequencing of SARS-CoV-2 isolates has led to the identification of single-point mutations and deletions, often having the recurrence of hotspots, associated with advantageous phenotypes. We report the isolation and molecular characterization of a SARS-CoV-2 strain, belonging to a lineage (C.36) not previously associated with concerning traits, which shows decreased susceptibility to vaccine sera neutralization.

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