Abstract:
:Since Streptococcus mutans is the principal etiologic agent causing dental caries, by encompassing an array of unique virulence traits, emerging treatment strategies that specifically target the virulence of this pathogen may be promising as alternative approaches compared to conventional antibiotic therapy. In this perspective, we investigated chloroform extract of cell-free culture supernatant from mangrove rhizosphere bacterium Bacillus amyloliquefaciens (MMS-50) in terms of anticariogenic properties of S. mutans, without suppressing its viability. Crude chloroform extract of MMS-50 was subjected to column and high performance liquid chromatographic techniques to obtain the active fraction (AF), and MMS-50 AF was used for all further assays. GC-MS and FT-IR were carried out to identify the major components present in MMS-50 AF. Comparative gene expression analysis of some biofilm-forming and virulence genes (vicR, comDE, gtfC, and gbpB) was done by real-time PCR. Cyclo(L-leucyl-L-prolyl) was found to be the chief compound in MMS-50 AF responsible for bioactivity. The minimum and maximum inhibitory concentrations of MMS-50 AF against S. mutans were found to be 100 and 250 μg/mL, respectively. Anti-virulence assays performed using below-sub-MIC levels of MMS-50 AF (30 μg/mL) resulted in significant reduction in adherence (68%), acid production, acid tolerance, glucan synthesis (32%), biofilm formation (53.5%) and cell surface hydrophobicity, all devoid of affecting its viability. The micrographs of CLSM and SEM further confirmed the antibiofilm and anti-virulence efficacies of MMS-50 AF. Expression data showed significant reduction in expression of all studied virulence genes. Thus, the current study unveils the anticariogenic potential of cyclo(L-leucyl-L-prolyl) from B. amyloliquefaciens, as well as its suitability as a novel and alternative anticariogenic agent against dental caries.
journal_name
Res Microbioljournal_title
Research in microbiologyauthors
Gowrishankar S,Poornima B,Pandian SKdoi
10.1016/j.resmic.2014.03.004subject
Has Abstractpub_date
2014-05-01 00:00:00pages
278-89issue
4eissn
0923-2508issn
1769-7123pii
S0923-2508(14)00032-1journal_volume
165pub_type
杂志文章abstract::Eight strains of acidophilic bacteria, isolated from mine-impacted and geothermal sites from different parts of the world, were shown to form a distinct clade (proposed genus "Acidibacillus") within the phylum Firmicutes, well separated from the acidophilic genera Sulfobacillus and Alicyclobacillus. Two of the strains...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2016.04.008
更新日期:2016-09-01 00:00:00
abstract::Bacteria of the genus Klebsiella are important opportunistic pathogens responsible for nosocomial infections that are increasingly resistant to antimicrobial agents. Distinctive identification of the species K. oxytoca, K. pneumoniae, K. planticola, K. ornithinolytica and K. terrigena is difficult based on phenotypic ...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/S0923-2508(03)00148-7
更新日期:2003-10-01 00:00:00
abstract::Randomly cloned fragments (in a size range 1 to 2.5 kb) of DNA from Bifidobacterium longum ATCC 15707, B. adolescentis CIP 64.59T, B. bifidum CIP 64.65 and B. animalis ATCC 25527 were used as hybridization probes to characterize strains of these species and distinguish them from closely related Bifidobacterium species...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(96)80271-3
更新日期:1995-01-01 00:00:00
abstract::Bacterial membranes are known to form domains with specific lipid compositions and functions. Recently, using membrane binding fluorescent dyes, lipid spiral structures extending along the long axis of the cell were detected. These spirals were absent when the synthesis of phosphatidylglycerol and cardiolipin was disr...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2010.07.006
更新日期:2010-11-01 00:00:00
abstract::In heap bioleaching and waste-rock dumps, complex microbial communities exist in the flowing and interstitial liquid phases and mineral surface-associated biofilms, often embedded in extracellular polymeric substances (EPS). Microbial activity in the interstitial phase and mineral ore surface facilitates mineral degra...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2020.09.002
更新日期:2020-01-01 00:00:00
abstract::Fungal dimorphism is the capacity of certain species of fungi to grow in the form of budding yeasts or mycelium depending on the environmental conditions. This characteristic is a complex phenomenon that involves modifications of the molecular machinery in response to different environmental signals. Through the use o...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2012.03.002
更新日期:2012-06-01 00:00:00
abstract::In this review, we synthesise current models and recent comparative genomic studies describing how bacterial species may emerge through adaptation to a new ecological niche and maintain themselves in the same niche over long time periods. We notably consider the impact of genetic exchange with phylogenetically close r...
journal_title:Research in microbiology
pub_type: 杂志文章,评审
doi:10.1016/j.resmic.2015.06.008
更新日期:2015-12-01 00:00:00
abstract::Ammonia-oxidizing archaea (AOA) and bacteria (AOB) are widely distributed in the natural environment and play crucial roles in the nitrification process and the removal of nitrogen (N). Although planktonic microbial community plays an important role in river biogeochemical cycles, few studies have attempted to address...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2014.08.003
更新日期:2014-10-01 00:00:00
abstract::Subtractive differential hybridization was used to identify genes in Bacillus subtilis that are induced by nutrient limitation. Several transcription units were identified. They exhibited increased transcription when cells were deprived of certain nutrients, such as glucose, ammonium, or phosphate, or when cells were ...
journal_title:Research in microbiology
pub_type: 杂志文章,评审
doi:10.1016/0923-2508(91)90059-j
更新日期:1991-09-01 00:00:00
abstract::Members of the genus Cronobacter are responsible for cases of meningitis and bacteremia with high fatality rates in neonates. Macrophage uptake of invading microbes is an innate process, and it has been proposed that macrophage infectivity potentiator (Mip) like proteins enhance the ability of pathogens to survive wit...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2015.02.005
更新日期:2015-04-01 00:00:00
abstract::Jarosite precipitates formed in iron oxidising bioreactors have been shown to harbour iron-oxidisers. The aim of this study was to develop an iron oxidising bioprocess where microorganisms are retained solely on biogenic jarosite particles. Based on preliminary experiments using a fluidised-bed bioreactor (FBR), the f...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2020.06.004
更新日期:2020-01-01 00:00:00
abstract::Evidence of increasing resistance to antibiotics in soil and other natural isolates highlights the importance of horizontal transfer of resistance genes in facilitating gene flux in bacteria. Horizontal gene transfer in bacteria is favored by the presence of mobile genetic elements and by the organization of bacterial...
journal_title:Research in microbiology
pub_type: 杂志文章,评审
doi:10.1016/s0923-2508(01)01215-3
更新日期:2001-06-01 00:00:00
abstract::As part of an ongoing study to determine the true habitat of Bacillus species, we report here the isolation and characterisation of Bacillus subtilis from the human gastrointestinal tract (GIT). Strains were obtained from ileum biopsies as well as from faecal samples and their biotypes defined. 16S rRNA analysis revea...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2008.11.002
更新日期:2009-03-01 00:00:00
abstract::The gene encoding a lipoprotein of 67 kDa, named P67, was cloned from Mycoplasma sp. bovine group 7 strain PG50 and expressed in Escherichia coli K12. Analysis of the amino acid sequence derived from the DNA sequence of the P67 gene revealed a typical prokaryotic signal peptidase II membrane lipoprotein lipid attachme...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/s0923-2508(97)83624-8
更新日期:1998-01-01 00:00:00
abstract::Both Neisseria meningitidis and Streptococcus pneumoniae are naturally transformable species and are known to be freely recombining in the wild. Large multilocus sequence typing (MLST) datasets have been generated for these species. Here we outline an approach which exploits these data sets in order to quantify the ex...
journal_title:Research in microbiology
pub_type: 杂志文章,评审
doi:10.1016/s0923-2508(00)00168-6
更新日期:2000-07-01 00:00:00
abstract::The response of Acidithiobacillus ferrooxidans ATCC 23270 to copper was analyzed in sulfur-grown cells by using quantitative proteomics. Forty-seven proteins showed altered levels in cells grown in the presence of 50 mM copper sulfate. Of these proteins, 24 were up-regulated and 23 down-regulated. As seen before in fe...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2014.07.005
更新日期:2014-11-01 00:00:00
abstract::Helicobacter spp. have been the focus of considerable research because of the role of this genus in gastrointestinal diseases. We infected NIH germ-free mice with Helicobacter trogontum, a recently described intestinal bacterium of rats, in order to study the distribution of this bacterium in the gastrointestinal trac...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/s0923-2508(99)80037-0
更新日期:1999-04-01 00:00:00
abstract::Total genomic DNA isolated by concentrating seawater and mercury-resistant bacteria were hybridized with a mer probe to detect the presence of homologous DNA sequences in marine coastal waters of the Bay of Bengal, India. Coastal water extracts induced with mercury hybridized with the mer operon of transposon Tn501. M...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(92)90026-k
更新日期:1992-03-01 00:00:00
abstract::The work described here continues our studies of the effects of subinhibitory concentrations of antibiotics on SOS and DNA repair gene expression in Staphylococcus aureus. Mitomycin C and the new-generation fluoroquinolone moxifloxacin induced expression of SOS response genes (lexA, recA, sosA, and umuC) in a ciproflo...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2009.09.013
更新日期:2009-12-01 00:00:00
abstract::Bacillus species as a group offer several advantages over other bacteria for protection against root pathogens because of their ability to form endospores, and because of the broad-spectrum activity of their antibiotics. The objectives of this work were to determine the ability of strains of Bacillus to inhibit Fusari...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2005.03.001
更新日期:2005-06-01 00:00:00
abstract::Sporulation histidine kinases, which sense sporulation-specific signals and initiate phosphorelay reactions, are poorly conserved among Bacillus species. We found several putative genes for sporulation histidine kinases in the genome sequence of Paenibacillus polymyxa E681 and assayed the genes for complementation of ...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2012.02.003
更新日期:2012-05-01 00:00:00
abstract::Vegetative incompatibility limits heterokaryon formation in fungi. It results from genetic differences at specific loci (het loci). Characterization of het genes and, more recently, of incompatibility reaction suppressors has, provided insight into the mechanisms involved. A link between development, vegetative incomp...
journal_title:Research in microbiology
pub_type: 杂志文章,评审
doi:10.1016/s0923-2508(00)00145-5
更新日期:2000-05-01 00:00:00
abstract::5-Mycoloyl-beta-arabinofuranosyl-(1-->2)-5-mycoloyl-alpha-ar abinofuranosyl-(1-->1')-glycerol, an antigenic glycolipid from the Mycobacterium avium-intracellulare complex (MAC) was examined for its applicability to the serodiagnosis of MAC infection by ELISA. Serum IgM antibody titres against this glycolipid in health...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(93)90048-7
更新日期:1993-03-01 00:00:00
abstract::There are several occasions when enumeration of Escherichia coli cells is needed. These include examination of urine specimens and water or food samples. Present methods rely on growth in more or less selective media (colony-forming units on agar or the most probable number method using liquid media). Unfortunately, n...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/s0923-2508(00)00222-9
更新日期:2000-09-01 00:00:00
abstract::Bacillus laterosporus is a spore-forming bacterium characterized by its ability to produce a canoe-shaped lamellar parasporal inclusion, adjacent to the spore. In some B. laterosporus strains crystalline inclusions of various shapes and sizes, which are released separately from spores during the lysis of the sporangiu...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(96)84709-7
更新日期:1996-06-01 00:00:00
abstract::The psychotrophic strain Pseudomonas fluorescens MFO is known to express several enzymatic activities in milk, including extracellular proteolytic activity, optimally when cells are grown at 17.5 degrees C. In order to study the nature of the mechanisms controlling the production of the extracellular protease, we devi...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(93)90064-9
更新日期:1993-10-01 00:00:00
abstract::This brief note reports the nucleotide sequences of the second nifH region of Methanobacterium ivanovii and of the two nifH regions of Methanosarcina barkeri 227. In the three cases, nifH is followed by two ORF (open reading frames) similar to ORF105 and ORF128 respectively, which were previously found downstream of M...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(91)90091-n
更新日期:1991-01-01 00:00:00
abstract::Mesophilic iron and sulfur-oxidizing acidophiles are readily found in acid mine drainage sites and bioleaching operations, but relatively little is known about their activities at suboptimal temperatures and in cold environments. The purpose of this work was to characterize the oxidation of elemental sulfur (S(0)), te...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2009.08.022
更新日期:2009-12-01 00:00:00
abstract::Ribosomal DNA (rDNA) polymorphism was compared to enzyme polymorphism and DNA/DNA hybridization data for the intraspecies differentiation of Providencia alcalifaciens. DNA from 27 strains previously classified into two zymotypes A1 and A2 and discriminated by two levels of DNA/DNA hybridization (delta Tm values of 0 t...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/0923-2508(91)90006-v
更新日期:1991-11-01 00:00:00
abstract::Deinococcus radiodurans is a bacterium best known for its extreme resistance to high levels of ionizing radiation. Gene expression profiles of D. radiodurans exposed to 0.3 M NaCl revealed that at least 389 genes were induced and 415 were repressed by twofold or more. A general down-regulation of the central metabolic...
journal_title:Research in microbiology
pub_type: 杂志文章
doi:10.1016/j.resmic.2013.07.005
更新日期:2013-11-01 00:00:00