@article {46672, title = {Inhibition of quorum sensing, motility and biofilm formation ofpseudomonas aeruginosaby copper oxide nanostructures}, journal = {Journal of Cluster Science}, volume = {32}, year = {2020}, month = {OCT}, pages = {1531 - 1541}, type = {Article; Early Access}, abstract = {

Quorum sensing (QS) is the communication between bacterial cells governed by their population density and regulated by the genes controlling virulence factors and biofilm formation. Multiple mechanisms of biofilms are resistive to antimicrobial chemotherapy; therefore novel strategies are required to overcome its limitations. Here, we report the effect of various copper oxide nanostructures (CuO-NSs) on quorum sensing inhibition. The two-dimensional CuO-NSs such as interlaced nanodiscs, nanodiscs and leaf-shaped nanosheets are prepared via a simple chemical method. The Quorum sensing inhibition (QSI) activity of all the CuO-NS are examined using reporter strainChromobacterium violaceumCV026 andEscherichia colipSB1142. We found that the CuO-interlaced nanodisc structures exhibit better QSI activity than nanodiscs and leaf-shaped sheets. The interlaced nanodisc structures are inhibited various long-chainN-acyl homoserine lactones (AHLs) mediated QS individually and confirmed by other QS-associated phenomena forPseudomonas aeruginosa, including biofilm inhibition, inhibition of virulence factors such as pyocyanin, protease production and swarming motility. Thus QSI activity of CuO-NSs is solely dependent on specific shape offering large surface area and more active sites. The CuO-NS is effective quorum sensing inhibitors, which has potential clinical applications in the management ofP. aeruginosaassociated infections.

}, keywords = {aeruginosa, Biofilm, Nanostructures, P, quorum sensing, Virulence factors}, isbn = {1572-8862}, issn = {1040-7278}, doi = {10.1007/s10876-020-01916-2}, author = {Desai, Dnyanada G. and Swarali, H. and Navale, Govinda R. and Prabhune, A. and Late, Dattatray J. and Dharne, Mahesh S. and Walke, Pravin S.} } @article {46726, title = {Pan-genomics of Ochrobactrum species from clinical and environmental origins reveals distinct populations and possible links}, journal = {Genomics}, volume = {112}, year = {2020}, month = {SEP}, pages = {3003-3012}, type = {Article}, abstract = {

Ochrobactrum genus is comprised of soil-dwelling Gram-negative bacteria mainly reported for bioremediation of toxic compounds. Since last few years, mainly two species of this genus, O. intermedium and O. anthropi were documented for causing infections mostly in the immunocompromised patients. Despite such ubiquitous presence, study of adaptation in various niches is still lacking. Thus, to gain insights into the niche adaptation strategies, pan-genome analysis was carried out by comparing 67 genome sequences belonging to Ochrobactrum species. Pan-genome analysis revealed it is an open pan-genome indicative of the continuously evolving nature of the genus. The presence/absence of gene clusters also illustrated the unique presence of antibiotic efflux transporter genes and type IV secretion system genes in the clinical strains while the genes of solvent resistance and exporter pumps in the environmental strains. A phylogenomic investigation based on 75 core genes depicted better and robust phylogenetic resolution and topology than the 16S rRNA gene. To support the pan-genome analysis, individual genomes were also investigated for the mobile genetic elements (MGE), antibiotic resistance genes (ARG), metal resistance genes (MRG) and virulence factors (VF). The analysis revealed the presence of MGE, ARG, and MRG in all the strains which play an important role in the species evolution which is in agreement with the pan-genome analysis. The average nucleotide identity (ANI) based on the genetic relatedness between the Ochrobactrum species indicated a distinction between individual species. Interestingly, the ANI tool was able to classify the Ochrobactrum genomes to the species level which were assigned till the genus level on the NCBI database.

}, keywords = {Antibiotic resistance, Average nucleotide identity, Clinical and environmental strains, Core genes, MinION, Virulence factors}, issn = {0888-7543}, doi = {10.1016/j.ygeno.2020.04.030}, author = {Gohil, Kushal and Rajput, Vinay and Dharne, Mahesh} } @article {47451, title = {Metagenomic analysis of a mega-city river network reveals microbial compositional heterogeneity among urban and peri-urban river stretch}, journal = {Science of the Total Environment}, volume = {783}, year = {2021}, month = {AUG }, pages = {146960}, type = {Article}, abstract = {

The rivers in the megacities face a constant inflow of extremely polluted wastewaters from various sources, and their influence on the connected peri-urban river is still poorly understood. The riverine system in Pune consists of Rivers Mula, Ramnadi, Pawana, Mutha, and Mula-Mutha, traversing through the urban settlements of Pune before joining River Bhima in the peri-urban region. We used MinION-based metagenomic sequencing to generate a comprehensive understanding of the microbial diversity differ-ences between the urban and peri-urban zones, which has not been explored at the meta scale until date. The taxonomic analysis revealed significant enrichment of pollution indicators microbial taxa (Welsch{\textquoteright}s t-test, p \< 0.05, Benjamini-Hochberg FDR test) such as Bacteriodetes, Firmicutes, Spirochaetes, Synergistetes, Euryarcheota in the urban waters as compared to peri-urban waters. Further, the peri-urban waters showed a significantly higher prevalence of ammonium oxidising archaeal groups such as Nitrososphaeraceae (Student{\textquoteright}s t-test p-value \<0.05 with FDR correction), thereby probably suggesting the influence of agricultural runoffs. Besides, the microbial community diversity assessment also indicated the significant dissimilarity in the microbial community of urban and peri-urban waters. Overall, the analysis predicted 295 virulence genes mapping to 38 different path-ogenic bacteria in the riverine system. Moreover, the higher genome coverage (at least 60\%) for priority patho-gens such as Pseudomonas, Klebsiella, Acinetobacter, Escherichia, Aeromonas in the sediment metagenome consolidates their dominance in this riverine system. To conclude, our investigation showed that the unre-strained anthropogenic and related activities could potentially contribute to the overall dismal conditions and in-fluence the connected riverine stretches on the outskirts of the city . (c) 2021 Elsevier B.V. All rights reserved.

}, keywords = {Industrialisation, Peri-urban, Riverine system, Urbanisation, Virulence factors}, issn = {0048-9697}, doi = {10.1016/j.scitotenv.2021.146960}, author = {Yadav, Rakeshkumar and Rajput, Vinay and Dharne, Mahesh} }