RESUMO
In the present study, a comprehensive proteomic analysis of Brucella melitensis (B. melitensis) strain ATCC23457 was carried out to investigate proteome alterations in response to in vitro-induced nutrient stress. Our analysis resulted in the identification of 2440 proteins, including 365 hypothetical proteins and 850 potentially secretory proteins representing ~77.8% of the B. melitensis proteome. Utilizing a proteogenomics approach, we provide translational evidence for eight novel putative protein-coding genes and confirmed the coding potential of 31 putatively annotated pseudogenes, thus refining the existing genome annotation. Further, using a label-free quantitative proteomic approach, new insights into the cellular processes governed by nutrient stress, including enrichment of amino acid metabolism (E), transcription (K), energy production and conversion (C), and biogenesis (J) processes were obtained. Pathway analysis revealed the enrichment of survival and homeostasis maintenance pathways, including type IV secretion system, nitrogen metabolism, and urease pathways in response to nutrient limitation. To conclude, our analysis demonstrates the utility of in-depth proteomic analysis in enabling improved annotation of the B. melitensis genome. Further, our results indicate that B. melitensis undergoes metabolic adaptations during nutrient stress similar to other Brucella. sp, and adapts itself for long-term persistence and survival.
Assuntos
Brucella melitensis , Proteômica , Brucella melitensis/genética , Proteoma , Aclimatação , NutrientesRESUMO
BACKGROUND: Human brucellosis is an important zoonotic disease of public health and often remains neglected owing to lack of sensitive and efficient diagnostic methods. This study evaluates diagnostic utility of in-house designed enzyme-linked immunosorbent assay (ELISA) using whole-cell antigens of Brucella abortus (B. abortus) S19 against the commercially available kits. METHODS: A prospective cohort study involving different populations within the Vidarbha regions of Maharashtra, India was conducted through camps organised from May 2009 to October 2015. A total of 568 serum samples were collected from high-risk people recruited as study cohorts based on inclusion criteria, additional risk factors and clinical symptoms. Samples were evaluated by indirect ELISA using the whole-cell antigens of B. abortus. The results were compared with the commercially available IgG detection ELISA kit to ascertain the specificity and sensitivity of the developed test. RESULTS: Fever, body ache, joint pain, lower back pain, loss of appetite and weight loss were major symptoms associated with the disease. With the cut-off of > 0.8, the positivity of brucellosis infection was at 12.32% (70/568) compared to 9.33% (53/568) as detected by the commercial kit. The in-house developed ELISA method yielded a sensitivity of 87.5% and specificity of 99.18% as compared to the commercial kits (sensitivity -80.30% and specificity -99.6%). DISCUSSION: The B. abortus S19-derived whole-cell protein-based ELISA is rapid and cost-effective and can be used for screening brucellosis infection in lieu of the commercially available ELISA kits.
RESUMO
We report here the draft genome sequence of Listeria monocytogenes CIIMS-PH-1, an isolate obtained from a 16-day-old infant with septicemia. The draft genome of CIIMS-PH-1 consisted of 2,939,183 bp and is a member of sequence type 308, clonal complex 1, and lineage I.