Contract TE no. 66/2010
Title: Molecular analysis of probiotic strains
antimicrobial activity mechanisms against urogenital infectious agents
Project director: Lecturer dr.
Diana Pelinescu (maiden name Smarandache)
Coordinating institution: University of Bucharest
Project budget: 680000
lei
Abstract
Urogenital infections
frequency, their high degree of recurrence and the extent of antimicrobial resistance of the
microorganisms require searching for new alternative strategies for the
prevention and treatment of these infections. The important progress of molecular biology during
last decades allowed to obtain valuable information on microbial ecosystems,
including gastrointestinal and urogenital tract and on the molecular mechanisms
involved in the complex interaction between microorganisms and the host. The
molecular aim the understanding of pathogenic activity of microorganisms and
also the beneficial effect of commensal microorganism such as lactic bacteria
on host health. Over the past years, probiotic therapy has been used for
prevention and treatment of many diseases. Although significant progress has
been done regarding the knowledge on probiotic effect of various microorganisms,
the mechanisms are not fully understood mainly due to the complex in vivo interaction. The
major objective of our project is the selection of probiotic lactic acid bacteria with antimicrobial
activity, represented either by the microbicides effect or by the ability to
inhibit or reduce expression of virulence and pathogenicity factors in pathogenic
bacteria and yeasts strains isolated from urogenital tract.
Operational objectives:
1. Isolation of new strains of lactic acid bacteria from various ecosystems
2. Isolation and identification of pathogenic strains by conventional and molecular taxonomy techniques
3. Screening test for identification of lactic acid bacteria strains with antimicrobial activity – microbicides effect
4. Evaluation of virulence and pathogenicity of pathogenic bacterial and yeast strains and selection of strains with high pathogenicity and virulence potential
5. Screening test for identification of lactic acid bacteria strains able to reduce the virulence and pathogenicity of pathogenic strains
6. Identification of selected lactic acid bacteria strains using polyphasic taxonomy techniques
7. Studies on the mechanisms involved in antimicrobial activity
8. Studies on gene expression of virulence and pathogenicity factors
1. Isolation of new strains of lactic acid bacteria from various ecosystems
2. Isolation and identification of pathogenic strains by conventional and molecular taxonomy techniques
3. Screening test for identification of lactic acid bacteria strains with antimicrobial activity – microbicides effect
4. Evaluation of virulence and pathogenicity of pathogenic bacterial and yeast strains and selection of strains with high pathogenicity and virulence potential
5. Screening test for identification of lactic acid bacteria strains able to reduce the virulence and pathogenicity of pathogenic strains
6. Identification of selected lactic acid bacteria strains using polyphasic taxonomy techniques
7. Studies on the mechanisms involved in antimicrobial activity
8. Studies on gene expression of virulence and pathogenicity factors
Scientific publications
1.
Ditu L.M.,
Chifiriuc M.C.,
Bezirtzoglou E.,
Voltsi C.,
Bleotu C.,
Pelinescu D.,
Mihaescu G.,
Lazar V., 2010, Modulation of virulence and antibiotic
susceptibility of enteropathogenic E. coli strains by Enterococcus faecium
probiotic strain culture fractions, Anaerobe 17(6), p. 448-451
2.
Cotar A.I.,
Chifiriuc M.C.,
Dinu S.,
Pelinescu D.,
Banu O.,
Lazăr V.,
2010, Quantitative
real-time PCR study of the influence of probiotic culture soluble fraction on
the expression of Pseudomonas aeruginosa quorum sensing genes, Roum. Arch. Microbiol. Immunol. 69 (4), p. 213 -223
3. Chifiriuc M.C.,
Badea Cioaca A., Lazar V., 2011,
In vitro assay of the antimicrobial activity
of kephir against bacterial and fungal strains, Anaerobe 17 (6), p. 433-435
4.
Sarbu I., Vassu T., Stoica I., Vamanu E.,
Pelinescu D.R., 2011, Selection of lactic
acid bacteria strains producing exopolysaccharides, European Biotechnology
Congress 2011, 28 sept – 1 oct, Istanbul, Turcia, publicat in Current Opinion
in Biotechnology, vol. 22 supplement 1,
p. S96 – S97
5.
Sarbu I., Vassu T., Sasarman E., Stoica I.,
Chifiriuc C.M., Ionescu R.A., Pelinescu
D.R., 2011, Antimicrobial activity
assessment of some lactic acid bacteria strains, FEMS 10th,
Symposium on Lactic Acid Bacteria, 28 aug-1 sept., Egmond Aan Zee, Olanda ,
E067
6. Sarbu I.,
Pelinescu D., Stoica I., Ionescu R., Dascalu L., Alexandru I., Chifiriuc M.C.,
Vassu T., Phenotypic profiles of virulence and antifungal resistance in different
Candida species isolated from vulvovaginal infections, Farmacia, in
press.
7. Cotar A.I., Chifiriuc M.C., Pelinescu D.,
Bezirtzoglou E., Voidarou C., Lazar V., The inhibitory activity of Lactobacillus paracasei probiotic culture
soluble fraction on the expression of Staphylococcus aureus agr genes quantified
by real-time RT-qPCR, trimis spre publicare in Current organic Chemistry
8.
Ionescu R., Tanase A-M, Sarbu I., Pelinescu D.,
Vassu T., Csutak O., Chiciudean I., Stoica I., 2012, Taxonomic identification of Pseudomonas strains producing
biosurfactants, 5th Croatian Congress of Microbiology with International
Participation 26 – 30 sept, Croatia, P5,
p.60.
9.
Sarbu I., Pelinescu D., Stoica I., Ionescu R.,
Marutescu L., Popa M., Chifiriuc C., Vassu T., Phenotpic virulence profile and taxonomic identification of microbial
strains isolated from urogenital infections, 5th Croatian Congress of
Microbiology with International Participation 26 – 30 sept , Croatia, P18,
p.73.
10.
Sarbu I., Vassu T., Stoica I., Ionescu R.,
Dascalu L., Popa M., Chifiriuc C., Pelinescu D., 2012, Antimicrobial activity of some lactic acid bacteria strains against
pathogenic strains isolated from urogenital infections, Central European Symposium on Antimicrobials
and Antimicrobial Resistance - CESAR 2012, 23 -26 sept, Croatia, p. 66.
Contract PCCA no.
77/2012
Title: Inovative, multidisciplinary research to
investigate the probiotic effects of new lactic acid bacteria strains and
consortia
Project director: Lecturer dr. Diana
Pelinescu (maiden name Smarandache)
Project budget: 2.000.000 lei
Abstract
The emergence of bacterial resistance and multiresistance to
antibiotics represent a major public health problem in Romania and also in the
entire world. In Romania, there is an increasing trend of the infections with
bacterial strains highly resistant to antibiotics, their prognosis being often
worsened by the production of bacterial biofilms on the tissues and
biomaterials used in medicine. Despite all these, in our country, the
development of new alternative strategies for the prevention and treatment of
the infections with multiresistant and biofilm forming bacteria is less
studied. The probiotic microorganisms have an important applicative potential
in biomedicine being of a great utility in the recovery of the balanced or
eubiosis state of the normal microbiota, after the negative impact of the
antibiotics on bacterial communities. A better understanding of mechanisms
involved in probiotic effect represents an important step for selection of
probiotic microorganisms. The selection of an appropriate microbial probiotic strain for a probiotic product should
be made on the basis of its ability to induce an improved host response, without
modifying the intestinal homeostasis.
The main goal of our project is the isolation and the
identification of probiotic strains (lactic acid bacteria - LAB) and the
establishing of the multispecific consortium, using an improved experimental
protocol designed for the selection based on anti-infective and
immunomodulatory activities of the probiotics for human use.
.Main
objectives
·
Selection of new LAB strains with probiotic effect belonging
to genera: Bifidobacterium, Lactobacillus, Lactococcus, Pediococcus and Straptococcus from
fermented food products and human origin.
·
Determination of the differences between the signals
induced by pathogens, non-commensally and commensally probiotic bacteria
involved in the activation of immune cells and observing the occurrence of
inflammatory immune responses or immunomodulatory effects.
·
Establishing of the optimal consortium
with enhanced antimicrobial and immunomodulatory
activity
·
In
vitro studies for establishing the efficient immune response
of the host cells consecutive to the orally ingested viable probiotic bacteria compared
to with administration of bacterial fractions
Project partners:
Coordinator: University of Bucharest, Faculty of Biology,
Department of Genetics
Partner 1: Institute
of Biology Bucharest
Partner 2: National Institute of Development – Research in
Biological Science Bucharest
Partner 3: University of Agronomic Science and Veterinary
Medicine Bucharest
Scientific publications
2012
Grosu – Tudor S.S., Zamfir M., 2012, “Functional properties of lactic acid
bacteria isolated from Romanian fermented vegetables”, II International
Conference on Antimicrobial Research, Lisabona, Portugalia, 21-23 noiembrie
2012, p. 563.
