Project description:Mycobacterium abscessus [M. abscessus (sensu lato) or M. abscessus group] comprises three closely related taxa with taxonomic status under revision: M. abscessus sensu stricto, M. bolletii and M. massiliense. We describe here a simple, robust and cost effective PCR-based method for distinguishing among M. abscessus, M. massiliense and bolletii. Based on the M. abscessus ATCC 19977T genome, discriminatory regions were identified between M. abscessus and M. massiliense from array-based comparative genomic hybridization. A typing scheme using PCR primers designed for four of these locations was applied to 46 well-characterized clinical isolates comprising 29 M. abscessus, 15 M. massiliense and 2 M. bolletii previously identified by multi-target sequencing. Interestingly, 2 isolates unequivocally identified as M. massiliense were shown to have a full length erm(41) instead of the expected gene deletion and showed inducible clarithromycin resistance after 14 days. We propose using this PCR-based typing scheme combined with erm(41) PCR for a straightforward identification of M. abscessus, M. massiliense and M. bolletii and assessment of inducible clarithromycin resistance. This method can be easily implemented into a routine workflow providing subspecies level identification within 24 hours of isolation of M. abscessus group. Two-color CGH with 4 independent Mycobacterium clinical isolates and the M massiliense type strain (CCUG 48898) labeled with Cy3 were cohybridized with the M abscessus type strain (ATCC 19977) labeled with Cy5 on a tiling array designed against the M abscessus type strain
Project description:Vir/pvpir genes, a multigene family in Plasmodium vivax that are a part of a larger superfamily of genes called the pir (Plasmodium interspersed repeat) genes have been reported earlier to be possibly involved in cytoadherence and evasion of splenic clearance. Plasmodium vivax, historically characterized as a "benign" malaria parasite, has been associated with clinical outcomes including hepatic dysfunction, renal failure, and cerebral malaria in India and several global regions. It constitutes an economic burden and presents a public health challenge alongside other Plasmodium species. Here, we present a part of global transcriptomic studies by custom designed microarray, that compare the transcriptome of the parasite responsible for severe Plasmodium vivax manifestations, specifically hepatic dysfunction and cerebral malaria from India, with an emphasis on the vir/pvpir genes, some of which are reported to play a role in cytoadherence. 23 patients with Plasmodium vivax malaria (Uncomplicated=6, Hepatic dysfunction=12 and Cerebral malaria=5) were subjected to microarray hybridization and the data so obtained showed a wide range of vir/pvpir subtelomeric subfamilies have been differentially expressed. Upregulation has been seen in 24 vir/pvpir genes in cerebral malaria samples (n=5) and 28 genes in hepatic dysfunction samples (n=12) belonging to different subfamily in at least 50% of the patient samples. Out of the upregulated vir/pvpir genes in cerebral malaria manifestation, members of vir subfamily E and pvpir H are maximum in number whereas in hepatic dysfunction manifestation, members of vir subfamily E and C comprise a significant proportion.
Project description:Actinotignum massiliense, a Gram-positive, facultatively anaerobic coccoid rod, is a rare human pathogen able to infect the urinary tract and belongs to the order of Actinomycetales. We identified A. massiliense as a resident of microbial biofilms growing on indwelling urethral catheter surfaces that were isolated from two patients with neurogenic bladders. These catheter biofilms (CBs) also harbored common uropathogens such as Proteus mirabilis and Aerococcus urinae, supporting the notion that A. massiliense depends on other co-colonizing microbes for survival. We isolated the bacterium from an anaerobically grown culture of a clinical sample, identified the species by 16S rRNA gene sequencing and verified this result via shotgun proteomics. Bacterial proteomes were profiled from the in vitro grown strain and four clinical ‘in vivo’ samples. The quantified proteomes allowed us to infer metabolic pathways and virulence/survival factors of importance in the CB milieu. Two putative subtilisin-like proteases, two Rib/Esp surface antigen repeat-containing proteins, a papain-like cysteine protease and a metal/heme/oligopeptide uptake system were highly expressed in vivo, but less so in vitro. We predict these proteins to be critical for adhesion and growth in CBs attacked by the host’s innate immune system or to improve bacterial fitness. Mixed acid fermentation following uptake and metabolism of xylose and glucuronate, sugars highly represented in proteoglycans and glycoglycerolipids of the urothelial mucosa and, in the case of glucuronate, shed into urine via renal xenobiotic conjugates, is inferred to be a major pathway for A. massiliense to generate energy under microaerobic conditions in CBs. The bacteria also appear to have active pathways for storage and utilization of glycogen as a carbon resource. Finally, we identified a putative polyketide synthase which may generate a secondary metabolite that interacts with either the host or co-colonizing organisms to enable A. massiliense survival in CBs.