Bio


My long-term scientific goal entails establishing an interdisciplinary and diverse laboratory focused on mitigating antibiotic resistance. My research comprises three central elements: elucidating the bacterial calcium transduction pathway, biosurfactants for treating deep tissue infections, and understanding how calcium signaling regulates bacterial pathogenesis mechanisms.

Stanford Advisors


Lab Affiliations


All Publications


  • Potential microbes for environment and agriculture: Bioengineering strategies for a sustainable future Biotechnology of Emerging Microbes Shyam, S. 2024
  • Antibiotic resistant genes in the environment-exploring surveillance methods and sustainable remediation strategies of antibiotics and ARGs. Environmental research Nava, A., Daneshian, L., Sarma, H. 2022: 114212

    Abstract

    Antibiotic Resistant Genes (ARGs) are an emerging environmental health threat due to the potential change in the human microbiome and selection for the emergence of antibiotic resistant bacteria. The rise of antibiotic resistant bacteria has caused a global health burden. The WHO (world health organization) predicts a rise in deaths due to antibiotic resistant infections. Since bacteria can acquire ARGs through horizontal transmission, it is important to assess the dissemination of antibiotic resistant genes from anthropogenic sources. There are several sources of antibiotic resistant bacteria and genes in the environment. These include wastewater treatment plants, landfill leachate, agricultural, animal industrial sources and estuaries. The use of antibiotics is a worldwide practice resulting in the evolution of resistance to antibiotics. Our review provides a more comprehensive look into multiple sources of ARG's and antibiotics rather than one. Moreover, we focus on effective surveillance methods of ARGs and antibiotics and sustainable abiotic and biotic remediation strategies for removal and reduction of antibiotics and ARGs from both terrestrial and aquatic environments. Further, we consider the impact on public health as this problem cannot be addressed without a global transdisciplinary effort.

    View details for DOI 10.1016/j.envres.2022.114212

    View details for PubMedID 36037921

  • Biosurfactant-assisted phytoremediation of potentially toxic elements in soil: Green technology for meeting the United Nations Sustainable Development Goals PEDOSPHERE Sonowal, S., Nava, A. R., Joshi, S. J., Borah, S., Islam, N. F., Pandit, S., Prasad, R., Sarma, H. 2022; 32 (1): 198-210
  • Ectopic growth of the Chaetothyriales fungal symbiont on <i>Ipomoea carnea</i> BOTANY Noor, A., Nava, A., Neyaz, M., Cooke, P., Creamer, R., Cook, D. 2021; 99 (10): 619-627
  • Evidence of Calcium Signaling and Modulation of the LmrS Multidrug Resistant Efflux Pump Activity by Ca2 + Ions in S. aureus. Frontiers in microbiology Nava, A. R., Mauricio, N., Sanca, A. J., Domínguez, D. C. 2020; 11: 573388

    Abstract

    Calcium ions (Ca2+) play a pivotal role in eukaryote cell signaling and regulate many physiological functions. Although a similar role for Ca2+ in prokaryotes has been difficult to demonstrate, there is increasing evidence for Ca2+ as a cell regulator in bacteria. The purpose of this study was to investigate Ca2+ signaling and the effect of Ca2+ on the Staphylococcus aureus multidrug resistant efflux pump LmrS. We hypothesized that antibiotics act by increasing Ca2+ concentrations, which in turn enhance the efflux activity of LmrS. These Ca2+ transients were measured by luminometry in response to various antibiotics by using the photoprotein aequorin reconstituted within live bacterial cells. Efflux associated with LmrS was measured by the increase in fluorescence due to the loss of ethidium bromide (EtBr) from both S. aureus cells and from E. coli cells in which the lmrs gene of S. aureus was expressed. We found that addition of antibiotics to cells generated unique cytosolic Ca2+ transients and that addition of CaCl2 to cells enhanced EtBr efflux whereas addition of Ca2+ chelators or efflux pump inhibitors significantly decreased EtBr efflux from cells. We conclude that antibiotics induce a Ca2+ mediated response through transients in cytosolic Ca2+, which then stimulates LmrS efflux pump.

    View details for DOI 10.3389/fmicb.2020.573388

    View details for PubMedID 33193178

    View details for PubMedCentralID PMC7642317

  • Biodegradation of bisphenol A by bacterial consortia isolated directly from river sediments ENVIRONMENTAL TECHNOLOGY & INNOVATION Sarma, H., Nava, A. R., Manriquez, A., Dominguez, D. C., Lee, W. 2019; 14
  • Mechanistic understanding and future prospect of microbe-enhanced phytoremediation of polycyclic aromatic hydrocarbons in soil ENVIRONMENTAL TECHNOLOGY & INNOVATION Sarma, H., Nava, A. R., Prasad, M. V. 2019; 13: 318-330
  • Evidence for nonpathogenic relationships of <i>Alternaria</i> section <i>Undifilum</i> endophytes within three host locoweed plant species BOTANY Noor, A., Nava, A., Cooke, P., Cook, D., Creamer, R. 2018; 96 (3): 187-200