A search of the gonococcal genome database using the known zinc-binding protein (znuA) sequences from Escherichia coli and Haemophilus influenzae identified an open reading frame encoding a putative gonococcal ZnuA. The consensus amino acid sequence of this open reading frame possessed a characteristic 30-amino acid histidine-rich metal-binding motif (repetitive HDH sequence) containing 43% histidine and 37% aspartic acid and glutamic acid. Subsequently, two adjacent open reading frames with homology to E. coli and H. influenzae znuB and znuC were located upstream of znuA. When partially purified from sonicated cell-free supernatants by CMSepharose chromatography, the mature gonococcal ZnuA had an estimated molecular mass of 38 kDa by SDS^PAGE. The presence of a DNA sequence encoding a 19-amino acid signal peptide and the solubility of the mature ZnuA suggested that this protein was located in the periplasm. Inactivation of the Neisseria gonorrhoeae F62 znuA by insertional mutagenesis resulted in a mutant that had a growth rate lower than that of the wild-type parent strain and that required high concentrations of ZnCl 2 (v200 WM) for optimal growth. Using a chemically defined agar medium, the gonococcal ZnuA mutant grew only in the presence of Zn 2 , whereas Mg
We analysed 528 genital self-collected swabs (SCS) from 67 HIV-1 and herpes simplex virus type-2 (HSV-2) co-infected women collected during the placebo month of a randomized crossover clinical trial of suppressive acyclovir in Chiang Rai, Thailand. In this first longitudinal study of HIV-1 and HSV-2 co-infected women using genital SCS specimens, we found frequent mucosal HIV-1 shedding. Overall, 372 (70%) swabs had detectable HIV-1 RNA with median HIV-1 viral load of 2.61 log(10) copies/swab. We found no statistically significant association between detectable HIV-1 RNA and HSV-2 DNA in the same SCS specimen (adjusted odds ratio [aOR] 1.40; 95% confidence intervals [CI], 0.78-2.60, P = 0.25). Only baseline HIV-1 plasma viral load was independently associated with genital HIV-1 RNA shedding (aOR, 7.6; 95% CI, 3.3-17.2, P < 0.0001). SCS may be useful for future HIV-1 and HSV-2 studies because this method allows for frequent genital sampling, and inclusion of genital sites other than the cervix.
Background Ocular syphilis cases continue to be identified in the United States since two clusters were reported in late 2014 into early 2015. Ocular syphilis (OS) is an inflammatory eye condition that can occur at any stage of syphilis with vision loss and blindness reported in some patients. We performed genotyping and whole genome sequencing (WGS) on Treponema pallidum strains from OS cases as part of molecular surveillance activities. Methods A total of 79 specimens from 57 patients with suspected or confirmed OS were received from 14 states between February 2016 and November 2020. Specimens included CSF, whole blood, serum, plasma, vitreous fluid, and a throat swab. T. pallidum DNA was detected with a real-time PCR assay targeting the polA gene. Genotyping was done using the four-component typing scheme (tpr E, G, & J; arp, tp0548, and tp0279). T. pallidum genomic DNA was enriched by selective whole genome amplification (SWGA) using Multiple Displacement Amplification (MDA) with custom oligonucleotides followed by WGS on an Illumina MiSeq v2 500 cycle platform. Results Twenty-three patients (40.4%) were MSM and HIV positive, respectively; 41 (71.9%) identified as White race, 4 (7%) Hispanic, and 3 (5.3%) Black. Twenty-three specimens from 18 (31.6%) patients tested positive for T. pallidum DNA. Thirteen of 23 (56.5%) specimens were CSF, while the remaining 10 included whole blood, serum, vitreous fluid, and a throat swab. Specimens from 3 patients were fully typed, revealing strain types 14b9g, 14d10g, and 14e9f. Six patients had partial genotypes. WGS was successful on 1 CSF and 2 vitreous fluid specimens from 2 cases resulting in 87% -98% genome coverage with at least 5 reads/site. Phylogenetic analysis showed that the 2 strains belonged to the Street 14 clade. Conclusions Our findings show that multiple strain types are responsible for ocular syphilis in the United States.
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