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C.
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Editorial
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1
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Contents
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2-6
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Review
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THE GENERATION OF
CODING SEQUENCES OF CELLULAR GENOME THROUGH COOPTION OF VIRAL GENES
Popov N. N., Sklyar N.I., Kolotova T. Yu., Davydenko M. B., Voronkina I. A.
This review attempts to summarize the available data concerning the
influence of viruses on the generation of the cellular genome coding genes
content. For a long time endogenous
retroviruses have been considered as selfish elements of the organism genome.
But now there is growing evidence that endogenous retroviruses are more than
genome junk and can serve as source for new coding sequences allowing organism
evolution. Many genes derived from
retroviruses have been identified in
eukaryote through comparative genomics and functional analyses. In particular,
genes derived from gag structural protein and envelope (env) genes, as well as
from the integrase-coding and protease-coding sequences, have been identified
in humans and other vertebrates. It has been proved that a number of these genes fulfill essential functions for the development
and survival of their host. One
of the best known co-opted
retroviral genes encoded syncytin plays a key
role in the placenta development. It is
interesting that during
mammalian evolution retroviral envelope genes have been domesticated several
times independently to generate syncytin. The activity-regulated cytoskeletal
protein Arc is important for cognitive functions and memory formation. Arc was one of over 100 human proteins that have been ‘‘domesticated’’ from
the retrotransposon remains of ancient viruses. A number of genes that code the transcription factors have emerged as a
result of “taming” the viral genes by the host organism. Now growing evidence reveals that
not only retroviruses but other RNA viruses are reverse-transcribed and
integrated into the genome of infected cells. It has been recently demonstrated
that all Homo sapiens bornavirus like nucleoproteins (EBLN) are expressed in at
least one tissue and consequently may have function.The co-option of the viral sequences not only can lead to the major
evolutionary innovations, but also is able to create interspecies polymorphism.What it has been described
here is probably only the tip of the iceberg, and future genome analyses will certainly
uncover new virus-derived genes.
Keywords: endogenous
retroviruses, Ty3/gypsy retrotransposon family, bornaviruses, adeno associated virus, SCAN domain, arc gene, syncytin.
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7-14
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CREATION OF NEW MEDICAL DRUGS BASED ON TRIZ AND COMPUTER MATHEMATICAL MODELING
Farber B.S., Martynov A.V., Kleyn I.R.
The article provides an overview of the current
state of the use of TRIZ in the pharmaceutical industry and our R&D efforts
in that area, based on TRIZ and computer mathematical modeling. Drug
development is one of the most important research areas, which affects almost
every family, and each one of us.
However, nobody in the world has used TRIZ as a philosophy of solving problems
in such important area as pharmaceutical research and development to develop
new efficient medical drugs. The application of the principles of TRIZ in this
arena opens up broad prospects in the creation of new classes of drugs that can
independently adapt to the patient's body. The combination of contradictions,
laws of development systems, algorithms, Su-field analysis, TRIZ principles,
deep fundamentals of pharmaceutical industry and pharmacology, modern computer
mathematical modeling, in the solution of each of the tasks at once, allows us
to achieve extraordinary results and obtain significantly more effective novel
drugs. For the first time in the World we have developed dynamic
self-organizing, quasi live drugs, based on the principles of TRIZ and
computerized mathematical modeling. These are drugs capable of adapting
independently both to the human body and to molecular targets, including
viruses, cancer cells and microorganisms.
We have created 17 new projects, however, in this article we illustrate
just 6 examples from our research and developments: 1. Novel directions to
fight multidrug resistant microorganisms.
2. Polymyxin with reduced nephrotoxicity. 3. Dynamic drugs: Dynamic
insulin. 4. Dynamic drugs: The dynamic anticancer drug Target-R to treat
different cancers. 5. Dynamic drugs:
Dynamic antiviral drug Albuvir. 6. Dynamic drugs: Hemostatic Gemma. Applying
TRIZ and mathematical modeling in pharmaceutical industry, produces novel and
future R&D trends. The proposed new
paradigm of combating infectious diseases using TRIZ led to the creation of a
unique pharmaceutical composition. The molecular modeling approach led to the
intensification of research and for synthesis of drugs based on simulated
inhibitor profiles. This increased the yield of novel dynamic drugs. The
dynamic drugs can overcome many problems from resistance to the slippage
effect, to eliminate the side effects of drugs. This will save millions of
lives. We deeply integrated TRIZ and computer mathematical modeling in our
R&D. In addition, our approach includes the application of the laws of
quantum physics and quantum chemistry; additionally, knowledge of the behavior
of molecules in different solutions and their interaction with each other at
different temperatures, in the presence of salts and other compounds. Really
effective drugs can be developed only on the basis of a systematic approach and
in-depth knowledge in the fields of medical, pharmaceutical physical chemistry,
analytical chemistry and pharmacognosy, chemistry of natural compounds, plant
medicine technology, biochemistry and molecular biology, pharmacology and many
other disciplines. Modeling these processes requires a large amount of not only
computer time, but also knowledge in a number of broad areas: from quantum
physics and chemistry to synthetic organic chemistry, in order to synthesize
engineered substances. Despite changes in the concept of drug development: from
banal screening (out of thousands of synthesized compounds, only one showed
biological activity) to those obtained as a result of molecular modeling
(another name is drug-design). (named as drug-design). The approach with the use of molecular
modeling led to the intensification of research - to the synthesis of drugs
based on simulated inhibitor profiles. This increased the yield of drugs - out
of every hundreds of the synthesized substances, one showed the expected
activity. The cost of pharmaceutical development software is currently quite
high and can even reach tens of millions of dollars. But this is a reasonable
amount, which makes it possible to obtain the required pharmaceutical
preparations, at least for known target proteins. However, for the design of
drugs of new generations at all stages of development - from building a model
of a target protein to creating a drug profile and its synthesis, TRIZ has not
been used systematically. Pharmaceutical industry is a huge area to be explored
by TRIZ.
Keywords: TRIZ, theory of inventive
problem solving, Altshuller, TRIZ in pharmaceutical industry and pharmacology,
Laws of technical systems evolution, problem solving, Su-field analysis,
drug-design, dynamic self-organizing, quasi live drugs, anti-cancer, antiviral,
multidrug bacterial resistance, antibacterial,
synergy.
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15-34 |
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Experimental works |
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THE MIMICRY ANTIGENS OF
BRONCHOPULMONARY SYSTEM AS FACTORS OF AUTOIMMUNE PROCESS INITIATION IN
CHILDHOOD BRONCHIAL ASTHMA
Chernuskiy V. G,. Popov N. N.,
Govalenkova O. L., Letyago A. V., Kashina-Yarmak V. L., Tolmachova S. R.,
Popova A. N.
Introduction. Microorganisms, isolated from the sputum of children with bronchial
asthma (BA) in the exacerbation period, are able to acquire mimicry antigens of
the trachea, bronchi and lung tissue, and have sensitizing effect on the
organism of the child not only through the truly microbial (viral) antigens,
but through the acquitted mimicry antigens of the cellular and tissue
structures of the bronchopulmonary system, thus shifting the pathological
process towards autoimmunity. Materials & methods. A microbiological
study of the sputum obtained from the 135 examined children with BA aged 6 to
14 years in the exacerbation period. The disease diagnosis was established
according to the protocol and directive of the Ministry of Health of Ukraine
from 08.10.2013 № 868. It was established that 45 children had non – atopic
asthma, 46 – mixed type asthma (MTBA) and 44 – atopic form of BA (ATBA).
Microbiological studies of the sputum were carried out with the help of the
commonly accepted methods: plating onto the solid and liquid culture mediums
with the subsequent strains isolation, microscopy, biochemical and serological
identification. Strains identification
was carried out according to the taxonomic tests of the Berge microorganism
index. In order to determine the presence of mimicry antigens in the examined
strains we have prepared hyperimmune rabbit serums to the trachea, bronchi, and
lung tissue antigens. Section samples obtained from the accidentally deceased
children with the І(0) blood type 2-4 hours after the moment of death
served as a antigenic material. Results & discussion. BA in children
is characterized by complex etiological structure that combines Gram-positive,
Gram-negative and Candida spp. fungi, and their associations. A comparative
study of the quantitative composition of the microorganisms isolated from the
sputum of the 135 examined children aged 5 to 14 years in the exacerbation
period was carried out. It was established that the following microorganisms
were isolated from the sputum of the children with ATBA with the lowest
frequency: S. pyogenes - 3 (6,8 ± 2,1%), S. aureus - 4 (9,1 ± 2,5%), and Е. coli — 5 (11,4 ± 2,3%); among associations - S.
aureus + S. pyogenes - 2 (4,5 ± 1,3%), S. aureus + P. mirabilis - 2 (4,5
±1,3%). The most frequent microorganisms were: С. albicans - 8 (18,2 ± 4,4%), P. aeruginosa - 7 (16,0 ± 4,2%), and among
associations - S. aureus + P. aeruginosa
- 4 (9,1 ± 2,5%), and S. aureus + E. coli-3(6,8 ±2,1%). In the children with
NABA, the least frequent microorganisms were: С. albicans fungi - 2 (4,4 ± 1,4%), as well as associations: S. aureus +
E. coli - 2 (4,4 ± 1,4%), and S. aureus + P. mirabilis - 3 (6,7 ± 1,7%), and
the most frequent - S. aureus 7 (15,2 ± 3,1%), P. aeruginosa - 7 (15,2 ± 3,1%),
as well as associations: S. aureus + S. pyogenes - 4 (8,7 ± 2,2 %) и S. aureus + P. aeruginosa - 4 (8,72 ± 2,2%). In
children with MTBA the lowest frequency of isolation from the sputum was
observed for: Рr. mirabilis - 3 (6,5±1,8 %) and Candida spp. fungi -
5 (10,9±4,1 %), among associations - S.aureus + E.coli- 2 (4,3±1,6%); S.aureus
+ P. mirabilis- 3 (6,5±1,8 %), the most frequent microorganisms were: S.aureus
- 7 (15,2±3,1 %), P.aeraginosa - 7 (15,2±3,1 %), and among associations:
S.aureus + S.pyogenes - 4 (8,7±2,2 %), and S.aureus + P. aeruginosa
-4(8,7±2,2%). The participation of the microflora isolated from the sputum in
the etiopathogenesis of the disease can be proven based on the determination in
their structure of the mimicry antigens of the trachea, bronchi and lung
tissue. It was experimentally proven in course of the study that in NABA the
titers of the agglutination of the organ specific serums with Gram-positive
microorganisms (Streptococcus and Staphylococcus) were 1:131 — 1:149, which
points out their decisive role in the etiopathogenesis in this form of BA,
while in the Gram-negative microorganisms, the background values of the titers
were observed - 1:17 - 1:85. In MTBA, the agglutination titer of organ specific
serums with Gram-positive microorganisms (Streptococcus and Staphylococcus) was
in the range (1:128 - 1:213), in Gram-negative microorganisms (E. coli and P.
aeruginosa) – (1:64 - 1:160), which points to the participation of the pyogenic
and Gram-negative microflora in the etiopathogenesis of this form of BA. In
ATBA, the results of agglutination reaction of organ specific serums with
Gram-positive microorganisms and Gram-negative microorganisms were in the range
of 1:18 - 1:44, the lowest range compared to the NABA and MTBA. It can be
concluded that microorganisms, isolated from the children with BA, are able
through inclusion into their structure the mimicry antigens of the trachea,
bronchi and lung structure, not only to determine the induction of the
pathological process, but also to shift it towards autoimmunity. Conclusion.
1. Independent of the BA form in children, the microbial factor has the
leading role in its etiopathogenesis, and can lead to the increased severity of
the disease course. 2. BA in children is characterized by complex etiological
structure that combines Gram-positive, Gram-negative, Candida spp. fungi, and
their associations. 3. Microorganisms isolated from the sputum of children with
BA, through varying their antigenic potential, are able to include into their
structure mimicry antigens of the cellular and tissue structure of the
bronchopulmonary system. 4. Microorganisms, through inclusion into their
structure the mimicry antigens of the trachea, bronchi and lung structure, not
only determine the induction of the pathological process, but also shift it
towards autoimmunity.
Keywords:
autoimmunity, mimicry antigens, asthma, children
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35-39
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CHARACTERISTICS OF THE
VIABILITY AND ACCORDANCE WITH THE TAXONOMIC STATUS OF THE LYOPHILIZED
SAMPLES
OF MUSEUM STRAINS OF ESCHERICHIA COLI ISOLATED IN 1946-1959 YEARS
Popov M.
M., Peretyatko O. G., Yagnuk Yu. A., Cholodna T. V. Effective microorganisms’ conservation with the aim of
long-term storage
of the strains in the collection without changes in the morphological,
physiological and genetical properties is provided by methods that
allow the
shift of the vegetative forms of bacterial cells into the anabiosis
state. The
most widespread among them is the lyophilization method. The museum of
microorganisms of the State Establishment “Mechnikov Institute of
microbiology
and immunology of the National Academy of Medical Sciences of Ukraine”
has one
of the oldest bacterial collections in Europe that consists of more
than 4000
lyophilized samples of microorganisms strains. The aim of
the study was the testing of viability and species
specific properties of the museum strains of E. coli,
that were preserved in lyophilized state long-term. Materials
and methods. The objects of
the study were the 30 lyophilized samples of the 22 strains of E. coli. Lyophilized cultures were
restored through dilution of the ampule content in the 1,0 ml nutritive
broth
and seeding of the microbial suspension from the 100-times dilutions
onto the
agar-based media (blood agar, Endo medium); the viability was
determined based
on the quantity of the colony forming units (CFU/ml).
Re-identification of the microbial cultures was carried out with
the use
of API system produced by «Bio-Mеrieux», France (ID 32 GN – for
enterobacteria identification). The phenotypic intra-strains
heterogeneity of the population was evaluated by dissociation index
that reflects the ratio (%) of the certain colony forms (S-, R-, D-, M-
forms)
compared to the total count. The statistical analysis was carried out
based on
the parametric statistic methods with the use of Microsoft Excel 2007
and STATISTICA
6.0 computer programs. Results and
discussion. There were (66,7±8,6) % of the
total amount of E. сoli strains
participating in the experiment that were able to be restored, and
therefore
those samples were selected for further studies. It was established
that the
quantity of the colonies on the solid nutritive media in the restored
strains
varied from 10^6 to 10^9 CFU/ml, the average survivability
parameter was (26,7±4,6) %. During the statistical analysis of the
results no
correlations between the CFU count and the storage term were
established (r=0). It was established that the majority of the
re-cultivated strains (90,0±3,8) % was characterized by dissociation
into
different colonial and morphological variants. The dissociation index
(ID)
values in the microbial populations of the studied Escherichia strains
varied
in the range of 10,0 % to 90,0 %. The statistical analysis of the data has
established the presence of correlation between the dissociation index
and term
of storage of the sample in the lyophilized state (r>0,95). The
established
colonial polymorphism of the studied strains of E. coli, in our
opinion,
is caused by adaptation to the stressful conditions and leads to the
increase
of the survivability of the bacterial population in course of the
long-term
storage in the lyophilized state. According to the re-identification
results, the majority (90,0±3,5) % of the samples corresponded
to the data indicated in the strains passport, except two strains that
did not
correspond to their initial identification based on the total of
biochemical
tests. Conclusions. The restoring of
the lyophilized cultures of E. coli
from 1946-1959 yy. of
isolation
the majority of samples was found to be viable and the viability varied
in the
range of 0,001 % to 100,0 %. It was established that the populations (90,0±3,8) % of restored strains were
characterized by dissociation into different colonial and morphological
variants. Based on the re-identification results of E. coli the correct
identification of strains was carried out and corrections were put in their passports. Further studies
perspectives. It is planned to
study the sensitivity to antibiotics of the collection strains of E.
coli,
isolated in the different periods of antibiotic use.
Keywords:
lyophilized samples, museum E. Coli
strains, viability, taxomic status.
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40-42
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DETERMINATION OF VAGINAL GEL COMPOSITION ON THE BASIS OF
BIOPHARMACEUTICAL AND RHELOGICAL RESEARCHES
Ivaniuk O.I., Yarnykh T.G., Hrudko V.O., Kovalevska I. V.
Aim. The aim of the
work is to determine the content of gelling agent in the composition of the
vaginal gel for the treatment of urogenital symptoms during the period of
women's hormonal instability and to determine the concentration of a
non-aqueous solvent propylene glycol in the gel to provide release of the
active ingredient, resveratrol. Materials
and methods. As objects of the study samples of gels with resveratrol and
hyaluronic acid with varying concentrations of gelling agent aristoflex AVC and
non-aqueous solvent propylene glycol have been taken. Biopharmaceutical studies
by equilibrium dialysis through a semipermeable membrane for 6 hours were
performed to select propylene glycol concentration. The optical density of the
samples obtained was determined using Evolution 60-S spectrophotometer. The
concentration of the gelling agent was determined by rheological performance
using the Rheolab QC rheometer, by Anton Paar, Austria. Results. In the course of the study, a comparison was made between
resveratrol release from samples with propylene glycol concentration of 10% and
15%. At 6th hour of the experiment, a larger amount of resveratrol, which has
passed to the solution, was observed in a sample with propylene glycol
concentration 15%. It has been established that an increase in the
concentration of propylene glycol contributes to an increase in the rate of the
active ingredient release from gel samples. Thus, for further studies on the
development of vaginal gel composition, the concentration of non-aqueous
solvent was chosen to be 15%. At the next stage, the choice of gel-former
concentration in the gel was made. In the course of the study, rheological
properties of samples with gel-former concentration of 1%, 1.5% and 2% have
been compared. The obtained rheograms of gel samples indicate that all systems
are coagulating with a pseudoplastic flow type and a certain degree of thixotropy.
A sample with the concentration of 1% is a liquefied system that has
practically no structure, as evidenced by the large difference between initial
and final viscosity. An increase in the concentration of gelling agent to 2%
leads to a strengthening of the structure. The sample with Aristoflex
concentration 1,5% has optimal rheological parameters that can provide high
biological availability of active substances.
Conclusions. It has been
established that the optimal concentration of PG, which contributes to maximal
release of the active substance, is 15% of the total mass of the sample.
According to the results of rheological research, the rational content of the
gel-former in the gel is 1,5%.
Keywords. Vaginal
gel, rheology, dialysis, resveratrol.
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43-47
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AGE-RELATED CHANGES OF SENSIBILIZATION PROFILES TO INDOOR INHALATION ALLERGENS
IN THE PATIENTS OF THE SOUTHERN REGION OF UKRAINE
Kurtova M.M., Koltsova I.H., Tarasov Yе.V., Blazhevich O.O.
Introduction: It is known that epidemiology of
allergic diseases is affected by range of plants, animal and insect allergens,
social and living conditions, nature of food habits of certain populations, sex
and age of patients. Age-related changes in immunological sensitization
profiles may also be geographically dependent. Thus, it is important to have
epidemiological data that characterizes a set of primary importance allergens
for different age groups for each particular geographic region. The purpose of
the study: Identify profiles of sensitization to household allergens, which
often cause respiratory manifestations of allergic diseases throughout the year
in patients of different age groups in the Southern region of Ukraine. Materials
and methods: Patients from Southern Region of Ukraine aged 1 to 84 years were
included in the study. During 2015-2018 years, we examined 2197 patients living
in the Southern region of Ukraine (Odessa and Mykolaiv regions) with suspected
respiratory allergic diseases and/or proven allergic diagnosis (pollinosis,
allergic rhinconjunctivitis and bronchial asthma) for presence of IgE
antibodies to household respiratory allergens by immunoblotting method. Results
& discussion: The highest percentage of positive reactions in whole pool of
patients was shown to mould Alternaria alternata (40,7%±1,0%), storage mite
Acarus siro (38,7%±1,3%) and domestic dust mite D.pteronyssinus (28,3%±0,9%).
First rise of antibodies to Alternaria alternata was registered from age 0-5 to
5-10 (46,3%±2,0% to 54,2%±2,6% respectively, p<0,05) and then were gradually
decreased up to age group 20-25 and stay at the same level during life.
Antibodies to dust mites and cat epithelium were gradually decreased with age,
in the same time antibodies to storage mites were gradually increased and
reached the highest percentage at the age 20-30 years (48,6%±4,2%). Conclusion:
Our study showed that in the Southern region of Ukraine antibodies to mouse and
rat epithelium was registered from early age in high levels: 37,1%±4,5% and
24,1±4,0% respectively. Level of antibodies to mould Alternaria alternata (m6)
in the Southern region of Ukraine was unexpectedly high. It was the highest
comparing to data from other countries. On the base of our data could be
proposed main target-allergens for examination of allergic patients in
different ages.
Keywords: allergy, indoor allergens,
household allergens, epidemiology of allergic diseases, sensibilization
profiles
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48-53
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DOCKING STUDY OF MOLECULAR MECHANISM BEHIND THE QUERCETIN INHIBITION OF MYCOBACTERIUM
TUBERCULOSIS UREASE
Lisnyak Yu. V., Martynov A. V.
Introduction. Mycobacterium
tuberculosis urease (MTU), being an
important factor of the bacterium viability and virulence, is an attractive
target for anti-tuberculosis drugs acting by inhibition of urease activity.
However, known urease inhibitors (phosphorodiamidates, hydroxamic acid
derivatives and imidazoles) are toxic and/or unstable, that prevent their
clinical use. Therefore, the development of novel efficient and safe MTU
inhibitors is necessary. To achieve this goal, we have chosen flavonoid
quercetin as a scaffold to develop new MTU inhibitors. Methods. Homology modeling. The target amino acid sequence of M. tuberculosis H37Rv urease was taken
from GenBank at NCBI. Homology model of M. tuberculosis urease was built as
described earlier by using molecular modeling program YASARA Structure. Amongst
the top-scoring templates, five high-resolution X-ray structures were selected
For each template five stochastic alignments were created and for each
alignment a three-dimensional model was built. Each model was energy minimized
with explicit water molecules using Yasara2 force field, and the models were
ranked by quality Z-score. From these 25 three-dimensional models obtained,
there was selected a model based on the template X-ray high-resolution
structure for S. pasteurii urease
(5G4H) which contained the flap in open state and had the highest quality score
amongst the nonamer structures (i.e. (αβγ)3
macromolecular ensembles). Search of inhibitor binding sites on the
surface of MTU. The search of inhibitor binding sites on the surface of
MTU was carried out by two steps. At first step, we used computational solvent
mapping method FTSite to identify a ligand binding sites on MTU surface. At
second step, docking of quercetin on MTU surface by AutoDock Vina implemented
in YASARA Structure was carried out within the ligand binding sites revealed by
FTSite. Mapping of protein surface by
FTSite method. Computational
solvent mapping method FTSite was used through the online server. FTSite server
outputs the protein residues delineating the first three binding sites. Molecular docking by AutoDock VINA. Docking of quercetin on the surface of M. tuberculosis urease by AutoDock VINA was carried within the binding sites previously
revealed by FTSite server. Docking was performead by using default parameters within a cubic 30 Å × 30 Å × 30 Å simulation cell centered on S atom of Cys 532
residue. The M. tuberculosis urease structure was kept rigid while the ligand
structure was flexible. The best hit of 25 runs having the lowest binding
energy was chosen as a final binding pose. An analysis of molecular
interactions and a representation of the results by molecular graphics were
done by YASARA Structure, LigPlot+ and PyMol. Results and discussion. In the best binding pose, quercetin
molecule is situated deep in the MTU cavity which leads to the active site
channel and near the active site flap. The circle B of quercetin is directed to
the active center, while the circle A is directed towards the exit from the
cavity. Binding energy and dissociation constant of quercetin complex with
urease is 8.7 Kcal/mol and 0.4 µМ, correspondingly. Ligand efficiency equals 0.4. The
binding of quercetin is provided by tight van der Waals contacts with eleven
residues two of which (Cys 532 and His 533) belong to the active site flap modulating transit of
substrate and products of catalysis through the active site channel. The
binding of quercetin is additionally stabilized by six hydrogen bonds with
residues Glu 376, Lys 379, Thr 380, Gly 490 and Ala 576. These intermolecular
interactions (through the tight contact with flap residues Cys 532 and, especially His 533) cause steric hindrance for the flap transition from
open to closed conformation thus fixing it in the open state that blocks
catalysis. Our model of quercetin binding to MTU corresponds to the results of
Xiao Z.-P. et al. which showed by enzyme kinetics and molecular docking that
quercetin is a noncompetitive inhibitor of Helicobacter
pylori urease and it is positioned near the active site flap as well
blocking it in the open conformation. As well, our model of quercetin binding
to urease corresponds to the results of Macomber L. et al. which showed by docking that quercetin binds
to the flap region of Klebsiella aerogenes urease. However,
our model disagrees with the proposed general mechanism of urease inhibition by
aromatic poly-hydroxylated inhibitors through the covalent binding with Cys
residue of the flap covering the active site. It may be a consequence of the
limitation of molecular docking methods used in our study that can explore only
non-bound interactions. Conclusions. Because
of the absence of experimental structure of M. tuberculosis urease its homology model was built and used in
further studies of ligand-urease interactions. It was revealed that quercetin
molecule is situated in the MTU cavity leading to the active site channel, near
the active site flap. The binding of
quercetin is provided by van der Waals contacts with eleven residues and by six
hydrogen bonds with urease residues. Based on the analysis of peculiarities of
quercetin binding with MTU, molecular mechanism of MTU inhibition by quercetin
was proposed. The model of quercetin binding with MTU corresponds well to the
results of docking studies on quercetin binding to Helicobacter pylori and Klebsiella aerogenes ureases. The results obtained expand the knowledge on the molecular
mechanisms of urease inhibition and contribute to the development of new
anti-tuberculosis immunomodulators.
Key words: Mycobacterium tuberculosis urease, urease inhibitors, quercetin,
molecular docking.
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54-60 |
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Short communication |
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INFLUENCE OF THE ENHANCERS ON THE
BACTERIOPHAGES ADAPTATION TO PSEUDOMONAS AERUGINOSA CLINICAL STRAINS
Derkach S.A., Martynov A.V., Kutsay N.M.,
Gorodnitskaya N.I. Gabysheva L.
Introduction. One of the areas of
treatment of infectious patients can be considered bacteriophage therapy. It is
known that phages have a high specificity, have a different level of lytic
activity, and are able to pass into a state of prophage, or adapt to the
circulating bacteria strain and acquire the ability to cause their lysis. The
purpose of this work was to obtain highly virulent bacteriophages by adapting
their moderately sensitive clones to clinical strains of P. aeruginosa. Materials and methods. The object of study was the culture of 15
strains of P. aeruginosa and 13
freshly isolated clinical strains). For experimental studies used commercial
preparations of bacteriophages (Microgen, Perm, Russia)). As enhancers, were
used: 1- (3,4-dimethoxybenzyl)
-6,7-dimethoxyisoquinoline (0.5 ml), 2.2 ', 2' ', 2' '- (4,8-di (piperidin-1
-yl) pyrimido [5,4-d] pyrimidine-2,6-diyl) bis (azanetriyl) tetraethanol (4
ml), 2- (Phenylmethyl) -1H-benzimidazole (1 ml), which previously showed the ability
to synergize to activate microbial growth. Determination of sensitivity to
specific bacteriophages was performed by the drip method. The adaptation
process included sequential bacteriophage passages in P. aeruginosa cultures, obtaining phage filtrate and release from
culture by centrifugation at 5000 rpm. Results
and discussion. The total number of strains that became sensitive to phages
under the action of adapted phages was 47%, and with enhancers – 67%. In 20.0 %
cases, there was a slight growth of secondary colonies (grade "+++")
after the 10th passage, and 2 cultures remained resistant to phages, both to
the original and adapted by both methods. Conclusion.
Thus, by adapting phages to clinical strains of P. aeruginosa, it was possible to increase their lytic activity by
3.5–5 times, which indicates the promise of using this method to obtain highly
effective phage preparations and phagolytic vaccines.
Keywords: Pseudomonas
aeruginosa, phages, stimulation of bacterial growth, enhancing of phages adaptation
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61-63 |
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