title: Changes in Caenorhabditis elegans immunity and Staphylococcal virulence factors during their interactions.
abstract: The nematode Caenorhabditis elegans is used as a model system for the study of host-pathogen interactions. Lipoteichoic acid (LTA) is one of the major virulent and immunostimulatory components found in gram positive bacteria. The current study used LTA isolated from Staphylococcus aureus and pathogenic and non-pathogenic Staphylococcus epidermidis. The overall physiological assays revealed that LTA exposed C. elegans show a significant reduction in the life span, production of eggs and progenies. To understand the involvement of innate immune specific players at the mRNA level, the regulation of few candidate antimicrobial genes was studied during Staphylococcal LTA exposures. qPCR analysis indicated an upregulation of antimicrobial peptides during LTA exposures. To understand the involvement of LTA and other virulent genes during infection, the regulation of LTA synthase and a few virulence genes was monitored during host exposure. The qPCR analyses indicated the upregulation of ltaS and other virulence genes (atoxin, sak, ssaA and fbe) during infection. Ability of the pathogens to modify their internal machinery during host presence was monitored by Fourier transform infrared spectroscopy, electrochemical impedance spectroscopy and cyclic voltametric analyses. The FTIR results indicated distinct alterations of peaks from Staphylococcal LTA composition between control and the host exposed. Further, EIS and CV data displayed clear differences between the host exposed Staphylococcal samples compared to their respective unexposed controls. The pathogenic and non-pathogenic strains showed different types of regulations and interactions during host exposures. The observed modifications clearly suggest that the Gram positive pathogen changes its LTA production and possibly the structure to cause a severe pathogenic effect on an interacting host.
authors.affiliation: Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 004, India.
authors.forename: Gnanasekaran
authors.initials: G
authors.lastname: JebaMercy
authors.affiliation: Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 004, India.
authors.forename: Udayakumar
authors.initials: U
authors.lastname: Prithika
authors.affiliation: Department of Bioelectronics and Biosensors, Alagappa University, Science Campus, Karaikudi 630 004, India.
authors.forename: Nehru
authors.initials: N
authors.lastname: Lavanya
authors.affiliation: Department of Bioelectronics and Biosensors, Alagappa University, Science Campus, Karaikudi 630 004, India.
authors.forename: Chinnathambi
authors.initials: C
authors.lastname: Sekar
authors.affiliation: Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 004, India. Electronic address: bsuryar@yahoo.com.
authors.forename: Krishnaswamy
authors.initials: K
authors.lastname: Balamurugan
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000276:immunology* / Q000382:microbiology* / Q000502:physiology; D004926:Escherichia coli / Q000502:physiology; D005298:Fertility; D008070:Lipopolysaccharides / Q000096:biosynthesis; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000472:pathogenicity*; D023421:Models, Animal; D010403:Penicillin Resistance; D013210:Staphylococcus / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity*; D013212:Staphylococcus epidermidis / Q000235:genetics / Q000472:pathogenicity*; D013682:Teichoic Acids / Q000096:biosynthesis; D037521:Virulence Factors / Q000235:genetics
chemical_list: D008070:Lipopolysaccharides; D013682:Teichoic Acids; D037521:Virulence Factors; C009900:lipoteichoic acid
keywords: Caenorhabditis elegans; Lipoteichoic acid; Staphylococcus species; Virulence genes