Phylogeography and transmission of Mycobacterium tuberculosis spanning prisons and surrounding communities in Paraguay.

Recent rises in incident tuberculosis (TB) cases in Paraguay and the increasing concentration of TB within prisons highlight the urgency of targeting strategies to interrupt transmission and prevent new infections. However, whether specific cities or carceral institutions play a disproportionate role in transmission remains unknown. We conducted prospective genomic surveillance, sequencing 471 Mycobacterium tuberculosis complex genomes, from inside and outside prisons in Paraguay's two largest urban areas, Asunción and Ciudad del Este, from 2016 to 2021. We found genomic evidence of frequent recent transmission within prisons and transmission linkages spanning prisons and surrounding populations. We identified a signal of frequent M. tuberculosis spread between urban areas and marked recent population size expansion of the three largest genomic transmission clusters. Together, our findings highlight the urgency of strengthening TB control programs to reduce transmission risk within prisons in Paraguay, where incidence was 70 times that outside prisons in 2021.

Vigilancia de la resistencia del Mycobacterium tuberculosis a los fármacos en Paraguay, 2014 a 2017 / Surveillance of drug resistance of Mycobacterium tuberculosis in Paraguay, 2014 to 2017

El objetivo del estudio fue identificar la resistencia del Mycobacterium tuberculosis a los fármacos en Paraguay, 2014 a 2017. Se realizó un estudio observacional retrospectivo. Se utilizaron los datos del Programa Nacional de Tuberculosis del Paraguay comprendidos entre los años 2014 a 2017. Se incluyeron todos los pacientes con diagnóstico de Tuberculosis que se realizaron un test de resistencia. Se extrajeron los datos en Excel y fueron analizados con Stata 17.0. Se incluyeron 3429 pacientes con tuberculosis que contaban con resultado de al menos una prueba de sensibilidad. La resistencia se encontró en 2.1% de los pacientes. La resistencia a la Rifampicina estuvo presente en el 0.3% de los casos mientras que a la Izionazida en el 0.6% de los casos. La prevalencia de resistencia fue más alta en hombres 3.4 (IC 95% 2.2 - 4.8) p=0.003, que residían en el chaco 6.0 (IC 95% 3.4 - 9.7) p=0.000, previamente tratados 2.7 (IC 95% 1.1 - 5.1) p=0.010. En el modelo se pudo observar que un paciente previamente tratado tiene mayores posibilidades de tener resistencia OR 2.62 (IC 95% 1.1 - 6.24). La prevalencia de resistencia del Mycobacterium tuberculosis a fármacos estuvo relacionada con haber sido previamente tratado

The objective of the study was to identify the resistance of Mycobacterium tuberculosis to drugs in Paraguay, 2014 to 2017. A retrospective observational study was carried out. The data from the National Tuberculosis Program of Paraguay between the years 2014 to 2017 were used. All patients with a diagnosis of Tuberculosis who underwent a resistance test were included. Data were extracted in Excel and analyzed with Stata 17.0. 3429 tuberculosis patients who had a result of at least one sensitivity test were included. Resistance was found in 2.1% of patients. Resistance to Rifampicin was present in 0.3% of cases while to Izionazide in 0.6% of cases. The prevalence of resistance was higher in men 3.4 (95% CI 2.2 - 4.8) p = 0.003, who resided in the Chaco 6.0 (95% CI 3.4 - 9.7) p = 0.000, previously treated 2.7 (95% CI 1.1 - 5.1) p = 0.010. In the model, it was observed that a previously treated patient has a greater chance of having resistance OR 2.62 (95% CI 1.1 - 6.24). The prevalence of resistance of Mycobacterium tuberculosis to drugs was related to having been previously treated

Hierarchy of Carbon Source Utilization in Soil Bacteria: Hegemonic Preference for Benzoate in Complex Aromatic Compound Mixtures Degraded by Cupriavidus pinatubonensis Strain JMP134.

Cupriavidus pinatubonensis JMP134, like many other environmental bacteria, uses a range of aromatic compounds as carbon sources. Previous reports have shown a preference for benzoate when this bacterium grows on binary mixtures composed of this aromatic compound and 4-hydroxybenzoate or phenol. However, this observation has not been extended to other aromatic mixtures resembling a more archetypal context. We carried out a systematic study on the substrate preference of C. pinatubonensis JMP134 growing on representative aromatic compounds channeled through different catabolic pathways described in aerobic bacteria. Growth tests of nearly the entire set of binary combinations and in mixtures composed of 5 or 6 aromatic components showed that benzoate and phenol were always the preferred and deferred growth substrates, respectively. This pattern was supported by kinetic analyses that showed shorter times to initiate consumption of benzoate in aromatic compound mixtures. Gene expression analysis by real-time reverse transcription-PCR (RT-PCR) showed that, in all mixtures, the repression by benzoate over other catabolic pathways was exerted mainly at the transcriptional level. Additionally, inhibition of benzoate catabolism suggests that its multiple repressive actions are not mediated by a sole mechanism, as suggested by dissimilar requirements of benzoate degradation for effective repression in different aromatic compound mixtures. The hegemonic preference for benzoate over multiple aromatic carbon sources is not explained on the basis of growth rate and/or biomass yield on each single substrate or by obvious chemical or metabolic properties of these aromatic compounds.

Involvement of several transcriptional regulators in the differential expression of tfd genes in Cupriavidus necator JMP134.

Cupriavidus necator JMP134 has been extensively studied because of its ability to degrade chloroaromatic compounds, including the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 3-chlorobenzoic acid (3-CB), which is achieved through the pJP4-encoded chlorocatechol degradation gene clusters: tfdCIDIEIFI and tfdDIICIIEIIFII. The present work describes a different tfd-genes expression profile depending on whether C. necator cells were induced with 2,4-D or 3-CB. By contrast, in vitro binding assays of the purified transcriptional activator TfdR showed similar binding to both tfd intergenic regions; these results were confirmed by in vivo studies of the expression of transcriptional lacZ fusions for these intergenic regions. Experiments aimed at investigating whether other pJP4 plasmid or chromosomal regulatory proteins could contribute to the differences in the response of both tfd promoters to induction by 2,4-D and 3-CB showed that the transcriptional regulators from the benzoate degradation pathway, CatR1 and CatR2, affected 3-CB- and 2,4-D-related growth capabilities. It was also determined that the ISJP4-interrupted protein TfdT decreased growth on 3-CB. In addition, an ORF with 34% amino acid identity to IclR-type transcriptional regulator members and located near the tfdII gene cluster module was shown to modulate the 2,4-D growth capability. Taken together, these results suggest that tfd transcriptional regulation in C. necator JMP134 is far more complex than previously thought and that it involves proteins from different transcriptional regulator families.

Involvement of several transcriptional regulators in the differential expression of tfd genes in Cupriavidus necator JMP134

Cupriavidus necator JMP134 has been extensively studied because of its ability to degrade chloroaromatic compounds, including the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 3-chlorobenzoic acid (3-CB), which is achieved through the pJP4-encoded chlorocatechol degradation gene clusters: tfdCIDIEIFI and tfdDIICIIEIIFII. The present work describes a different tfd-genes expression profile depending on whether C. necator cells were induced with 2,4-D or 3-CB. By contrast, in vitro binding assays of the purified transcriptional activator TfdR showed similar binding to both tfd intergenic regions; these results were confirmed by in vivo studies of the expression of transcriptional lacZ fusions for these intergenic regions. Experiments aimed at investigating whether other pJP4 plasmid or chromosomal regulatory proteins could contribute to the differences in the response of both tfd promoters to induction by 2,4-D and 3-CB showed that the transcriptional regulators from the benzoate degradation pathway, CatR1 and CatR2, affected 3-CB- and 2,4-D-related growth capabilities. It was also determined that the ISJP4-interrupted protein TfdT decreased growth on 3-CB. In addition, an ORF with 34% amino acid identity to IclR-type transcriptional regulator members and located near the tfdII gene cluster module was shown to modulate the 2,4-D growth capability. Taken together, these results suggest that tfd transcriptional regulation in C. necator JMP134 is far more complex than previously thought and that it involves proteins from different transcriptional regulator families (AU)

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