Head: Assoc. Prof. Nadya Markova, MD, PhD

Tel.: +359 2 979 31 61


Author ID Scopus (ScienceDirect): 7006844985



Assoc. Prof. d-r Violeta Valcheva

Tel.: +359 2 979 31 61


Author ID Scopus (ScienceDirect): 14061470900, Valcheva, Violeta


Technician Albena Cherneva

Tel.: +359 2 979 31 61




⦁ Molecular epidemiology, phylogenetics and evolution of mycobacteria (DNA isolates from Mycobacterium tuberculosis complex : Mycobacterium tuberculosis and Mycobacterium bovis).

⦁ Application of bioinformatics tools for analysis of mycobacteria.

⦁ Screening of newly synthesized compounds for their in vitro antimycobacterial activity.

⦁ Mycobacteria and L-transformation, latent tuberculosis, BCG vaccine, placental microbiome and immunological phenomenon during pregnancy & blood microbiota

⦁ Development of molecular-biological tools for detection and identification of mycobacterial L-forms.

⦁ Molecular mechanisms of drug resistance and tolerance in mycobacteria.


  • Molecular epidemiology, phylogenetics and evolution of mycobacteria:


Valcheva, V., Savova-Lalkovska T., Vyazovaya A., Dimitrova A. Bonovska M., Najdenski H. First insight into phylogeography of Mycobacterium bovis and M.caprae from cattle in Bulgaria, Infection, Genetics and Evolution2020, 81: 104240 doi: 10.1016/j.meegid.2020.104240 IF:2.611 Q2


Savova, T., Petrova, R., Valcheva, V.Bonovska, M.Najdenski, H. Isolation of Mycobacterium avium subsp. paratuberculosis from mouflon in Bulgaria. Russian Journal of Infection and Immunity2019, 9(5-6): 665-670. doi: 10.15789/2220-7619-2019-5-6-665-670 SJR 0,13, Q4


Bonovska, M., Savova T., Petrova R., Valcheva V.Najdenski H. Cases of paratuberculosis in deer in Bulgaria. Comptes Rendus de Lacademie Bulgare des Sciences2019, 72 (3): 422-428, doi:10.7546/CRABS.2019.03.18, IF: 0.321, Q2


Yanev, S., Stoyanova, T., Valcheva V., De Montellano, O. Xanthates: Metabolism by Flavoprotein-Containing Monooxygenases and Antimycobacterial Activity. Drug Metabolism and Disposition2018. 46(8), 1091-1095. DOI:10.1124/dmd.118.081984, 1091-1095 IF:3.64   Q1


Philipova, I., Valcheva, V., Mihaylova, R., Mateeva, M., Doytchinova, I. and Stavrakov, G., Synthetic piperine amide analogues with antimycobacterial activity. Chem biology & drug design. 2017. doi: 10.1111/cbdd.13140 IF:2.396 Q1


Angelova, V., Valcheva, V., Pencheva, T., Voynikov, Y., Vassilev, N., Mihaylova, R., Momekov, G., Shivachev, B. Synthesis, antimycobacterial activity and docking study of 2-aroyl-[1] benzopyrano [4, 3-c] pyrazol-4 (1H)-one derivatives and related hydrazide-hydrazones. Bioorg Med Chem Lett2017. 27 (13): 2996-3002. doi: 10.1016/j.bmcl.2017.05.011 IF:2.454 Q1


Mokrousov, I., Vyazovaya, A., Iwamoto, T., Skiba, Y., Pole, I., Zhdanova, S., Arikawa, K., Sinkov, V., Umpeleva, T., Valcheva, V., Alvarez Figueroa, M., Ranka, R., Jansone, I., Ogarkov, O., Zhuravlev, V., Narvskaya, O. Latin-American-Mediterranean lineage of Mycobacterium tuberculosis: Human traces across pathogen’s phylogeographyMolecular Phylogenetics and Evolution2016, 99:133-143. doi: 10.1016/j.ympev.2016.03.020. IF 3.916 Q1 


Mokrousov, I., Chernyaeva, E., Vyazovaya, A., Skiba, Y., Solovieva, N., Valcheva, V., Levina, K., Malakhova, N., Jiao, W.W., Gomes, L.L. and Suffys, P.N., A rapid assay for detection of the epidemiologically important Central Asian/Russian strain of the Mycobacterium tuberculosis Beijing genotype. J Clin Microbiol. 2017. pii: JCM.01551-17. doi: 10.1128/JCM.01551-17  IF:2.44 Q1


Stavrakov, G., Valcheva, V., Voynikov, Y., Philipova, I., Atanasova, M., Konstantinov, S., Doytchinova, I. Design, Synthesis, and Antimycobacterial Activity of Novel Theophylline‐7‐Acetic Acid Derivatives with Amino Acid Moieties. Chem biology & drug design2016. 87(3):335-41. doi: 10.1111/cbdd.12676 IF 2.48 Q1


Valcheva, V., Rastogi, N., Mokrousov, I. Prevalence of Latin-American-Mediterranean genetic family in population structure of Mycobacterium tuberculosis in Bulgaria. International Journal of mycobacteriology2015, 4(1): 22-23

doi:10.1016/j.ijmyco.2014.10.044 IF 0,167 Q3


  • Mycobacteria and L-transformation, latent tuberculosis, BCG vaccine, placental microbiome, immunological phenomenon during pregnancy & blood microbiota:

Markova, N. Eubiotic vs. dysbiotic human blood microbiota: the phenomenon of cell wall deficiency and disease-trigger potential of bacterial and fungal L-forms. Discovery Medicine. Jan-Feb 2020;29(156):31-40.


Markova, N. Dysbiotic microbiota in autistic children and their mothers: persistence of fungal and bacterial wall-deficient L-form variants in blood. Scientific Reports. 2019 Sep 16;9(1):13401. doi: 10.1038/s41598-019-49768-9.


Markova, N. L-form bacteria cohabitants in human blood: significance for health and diseases. Discovery Medicine. 23 (128): 305-313, May 2017                                                                      


Dimova, T.,  Terzieva, A, Djerov, L, Dimitrova,V  Nikolov, A , Grozdanov,P and  Markova N. Mother-to-newborn transmission of mycobacterial L-forms and Vδ2 T-cell response in placentobiome of BCG-vaccinated pregnant women.” Scientific reports 7, no. 1 (2017): 1-11.


Markova, N., Slavchev, G., Djerov, L., Nikolov, A., Dimova, T. Mycobacterial L-forms are found in cord blood: A potential vertical transmission of BCG from vaccinated mothers. Human Vaccines & Immunotherapeutics2016, 12: 2565-2571.


Markova, N., Slavchev, G, Michailova, L. Presence of mycobacterial L-forms in human blood: Challenge of BCG vaccination. Human Vaccines & Immunotherapeutics2015, 11: 1192-200.



Molecular Genetic Research :

  • The first for Bulgaria molecular genetic research in the field of animal husbandry was conducted on the genetic diversity of Mycobacterium bovis strains circulating in Bulgaria, which will support the development of molecular epidemiology in veterinary medicine. Information has been added to the global database of Bulgarian Mycobacterium bovis
  • For the first time in 40 years in Bulgaria, an in-depth comprehensive study for the presence of paratuberculosis in deer and mouflon was conducted. The characteristic pathoanatomical changes established for paratuberculosis were confirmed during the histological, microbiological and molecular genetic studies.
  • More than 200 new diverse chemical structures were synthesized, including more than 50 chiral compounds derived from the natural terpenoids (+) – camphor and (-) – fenhon. Some of their biological and pharmacological activities have been screened.
  • By applying the approaches of molecular modeling to characterize the relationship between the structure of the newly synthesized chemical compounds and their biological effect (QSAR model and molecular docking) the contribution of the individual structural fragments in the obtained compounds to their antimycobacterial activity is proved.
  • Compounds with an R-2-amino-1-butanol motif, camphor-linked amino alcohols and amidodiols as well as coumarin containing hydrazide-hydrazone analogs are promising compounds for further development of new antituberculosis agents.


Blood microbiota:

  • Valuable insight and experience in the field of bacterial L-forms (cell wall-deficient forms); their formation and persistence in hosts, as well as their importance for latent infections, allergic, autoimmune, neurodegenerative diseases and autism spectrum disorders.
  • Strong background about innovative methodology concerning cultivation, isolation and identification of L-forms (cell wall deficient variants of bacteria and fungi) from human blood and assessment of blood microbiota.