Salmonella is an intracellular pathogen infecting a wide range of hosts and can survive in macrophages. An essential mechanism used by macrophages to eradicate Salmonella is production of reactive oxygen species. Here, we used proteogenomics to determine the candidate genes and proteins that have a role in resistance of S. Typhimurium to H2O2. For Tn-seq, a saturated Tn5 insertion library was grown in vitro under either 2.5 (H2O2L) or 3.5 mM H2O2 (H2O2H). We identified two sets of overlapping genes required for resistance of S. Typhimurium to H2O2L and H2O2H, and the results were validated via phenotypic evaluation of 50 selected mutants. The enriched pathways for H2O2 resistance included DNA repair, aromatic amino acid biosynthesis (aroBK), Fe-S cluster biosynthesis, iron homeostasis and a putative iron transporter system (ybbKLM), and H2O2 scavenging enzymes. Proteomics revealed that the majority of essential proteins, including ribosomal proteins, were downregulated upon exposure to H2O2. On the contrary, a subset of conditionally essential proteins identified by Tn-seq were analyzed by targeted proteomics, and 70% of them were upregulated by H2O2. The identified genes will deepen our understanding on S. Typhimurium survival mechanisms in macrophages, and can be exploited to develop new antimicrobial drugs.
Oil and gas industry operates according to stringent standards that primarily strive to keep the pipeline transportation and other related operations efficiently while maintaining and practicing high standards of industrial safety. Due to which, the routine inspection and maintenance of underground/overground structures became a challenging process. Over the years, performance based integrity management programmes became popular and it have been implemented for managing the safety and environmental risks associated with hazardous oil or gas pipelines. Pipeline safety and integrity team must verify, repair and certify the integrity of pipelines that could leak or failure in the future. Internal inspection using pipeline inspection gauges (PIG) are considered expensive and the need for surface preparation procedures makes the inspection operations time consuming. Whereas, external survey operations are carried out by highly trained and certified inspection/survey team where they manually identify pipeline leakages or any visible damages. External manual inspection is conducted using various handheld devices and recorded data is later analyzed to identify and locate the possible anomalies. Relatively high surrounding temperatures and uneven terrain makes the manual survey a mundane mission. The shortcomings and the challenges of the conventional external inspection and survey mechanisms are tackled by introducing a mobile robotic platform equipped with non-invasive magnetometric diagnosis (NIMD) system which allows non-contact anomaly detection from a distance of up to 2-3m from the underground pipeline metal core without unearthing or any surface treatments such as coating removal that are performed in the conventional techniques. The proposed autonomous pipeline inspection system has various sensors that can precisely locate, navigate and detect the underground pipeline faults. A novel hierarchical controller which was developed in our previous studies was utilized and employed for the navigation of vehicle over the buried infrastructures. The effectiveness and the performance of autonomous system was tested on real field conditions and the true ability of the system was showcased to detect the underground pipeline anomalies even in extreme environmental conditions.
24Salmonella is an intracellular pathogen that infects a wide range of hosts and can survive in 25macrophages. An essential mechanism uses by the macrophages to eradicate Salmonella is 26 production of reactive oxygen species. Here, we used proteogenomics to determine the candidate 27 genes and proteins that have a role in resistance of S. identified by Tn-seq were analyzed by targeted proteomics, and 70 % of them were upregulated 37 upon exposure to H 2 O 2 . The identified candidate genes will deepen our understanding about 38 mechanisms of S. Typhimurium survival in macrophages, and can be exploited to develop new
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.