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Dr.
Mikhail Alexeyev |
Assistant Professor Ph.D., Molecular
Biology, Institute of Molecular Biology and Genetics
of the National Academy of Sciences of Ukraine.
Kiev, Ukraine
Postdoctoral, Texas Heart Institute |
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Dr.
Mikhail F. Alexeyev, assistant professor
of pharmacology at the University of South Alabama,
was awarded a two-year grant of $100,000 from the
United Mitochondrial Disease Foundation (UMDF) on
Sept. 18, 2002.
This research project will study the selective
elimination of defective mitochondrial genomes
as an approach to find a potential reversal for
inherited mitochondrial diseases, Neuropathy Ataxia
Retinis Pigmentosa (NARP) and Maternally Inherited
Leigh Syndrome (MILS).
Out of 51 studies submitted, Professor Alexeyev’s
is one of six proposals UMDF selected to fund.
A review panel of researchers and clinicians thought
the six proposals displayed the strongest science
and greatest impact on the field of mitochondrial
medicine and research. |
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Dr. Mikhail
F. Alexeyev receives an award. |
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People
attending the reception. |
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| Research
Publications
Presentations
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| Research |
| Mitochondria are the powerhouse
of the cell. They are believed to be direct descendants
of a bacterial endosymbiont that became established
at an early stage in a nucleus-containing (but
amitochondriate) host cell.
The presence of DNA in mitochondria (mtDNA) was
described almost 40 years ago. In humans, mtDNA
is about 16,569 bp (base pairs) long and encodes
13 polypeptides, 2rRNA and 22 tRNA genes. The
number of polypeptides in the mitochondrial proteome,
on the other hand, has been estimated to be as
high as 1000. Therefore, most structural proteins
and enzymes in mitochondria are encoded by the
nuclear genome and are synthesized on cytoplasmic
ribosomes. The import of these proteins can occur
post-translationally, through the use of mitochondrial
targeting sequences (MTS).
It was not until 1988 that mutations in mtDNA
were associated with defined human pathologies.
According to recent estimates, pathogenic mtDNA
defects affect as much as 1 in 15,000 of the adult
population. Cells which are highly dependent on
oxidative phosphorylation (e.g. neurons, cardiac
cells and skeletal muscle cells) are most sensitive
to accumulation of mtDNA defects and therefore
are most often affected by mitochondrial disease.
mtDNA, unlike nuclear DNA, is not protected by
histones and, as a consequence, is more susceptible
to damage inflicted by different agents, most
notably by reactive oxygen species (ROS) generated
as a result of electron leakage from the respiratory
chain or in response to environmental stress.
Accumulation of such damage is believed to be
a basis for ageing and acquired mitochondrial
diseases. Mutations in mtDNA accumulate as one
ages and hence, depending on the environmental
stress, an individual can reach a threshold for
manifestation of the disease during infancy, adolescence
or adulthood.
In any given cell, the fraction of mutant mitochondrial
genomes can vary from 0 to 100%. These two extreme
conditions are called homoplasmy as opposed to
heteroplasmy, when cell has a mixed population
of normal and mutant mitochondrial genomes. Factors
that lead to the establishment and maintenance
of heteroplasmy are currently unknown.
Therefore, I am interested in the biochemical
mechanisms used by mitochondria to repair the
mtDNA damage and in how deficiencies in these
mechanisms lead to pathological changes in the
function of cardiac muscle and vascular endothelium,
in the cross-talk between nuclear and mitochondrial
genomes, in the establishment and maintenance
of heteroplasmy and in the developing experimental
approaches to manipulate heteroplasmy and mtDNA
in general in mammalian cells for the purpose
of treatment of mitochondrial disorders.
My second area of interest is the role of the
Eph-Ephrin signaling in the vascular morphogenesis
and pathology. Eph receptors, the largest family
of receptor tyrosine kinases (RTKs), are unique
among RTKs in that they interact with cell-surface
bound (as opposed to soluble) ephrin ligands,
in that in many cases such interaction induces
signaling cascades in both interacting cells (bi-directional
signaling) and in that eph signaling does not
promote cellular proliferation. The targeted disruption
of either EphB4 or its ligand, Ephrin B2, leads
to defects in vascular remodeling and is embryonically
lethal in mice. Therefore, we believe that signaling
through Eph receptors is critically involved in
vascular remodeling in various pathologies of
pulmonary vasculature.
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| Publications |
M.F. Alexeyev and H.H. Winkler.
Tranposable Dual Reporters for Studying the Structure-Function
Relationships in Membrane Proteins: Permissive
Sites in R. Prowazekii
ATP/ADP Translocase. Biochemistry 41:406-414
(2002).
Alexeyev, M.F. and Winkler, H.H. Transposable
Dual Reporters for Studying the Structure-Function
Relationships in Membrane Proteins: Permissive
Sites in R. prowazekii ATP/ADP Translocase Biochemistry
41 (2002) 406-414.
Alexeyev, M.F. and Winkler, H.H. Survey of positively
charged residues in Rickettsia prowazekii ATP/ADP
translocase. Submitted.
Gireesh Rajashekara, Mikhail F. Alexeyev, Shirin
Munir, Alberto Back, David A. Halvorson, Kakambi.
V. Nagaraja and Carol L. Wells. Pathogenic role
of SEF14, SEF17, and SEF21 fimbriae in salmonella
enterica serovar enteritidis infection of chickens.
Appl Environ Microbiol. April, 2000 66(4):1759-63.
Alexeyev, M.F. and Winkler, H.H. Gene synthesis,
expression and purification of Rickettsia prowazekii
ATP/ADP translocase. Biochim. Biophys. Acta. 1419
(1999) 299-306.
Alexeyev, M.F. The pKNOCK series of broad-host-range
mobilizable suicide vectors for gene knockout
and targeted DNA insertion into the chromosome
of Gram-negative bacteria. BioTechniques 26 (1999)
824-828.
Alexeyev, M.F. and Winkler, H.H. Membrane topology
of the Rickettsia prowazekii ATP/ADP translocase
revealed by novel dual pho-lac reporters. J. Mol.
Biol. 285 (1999) 1503-1513.
Balbas P., Alexeyev M., Shokolenko I., Bolivar
F. and Valle F. A pBRINT family: plasmids for
insertion of cloned DNA fragments into the Escherichia
coli chromosome. Gene 172 (1996) 65-69.
Alexeyev, M.F., Shokolenko, I.N. and Croughan,
T.P. New mini-Tn5 derivatives for insertion mutagenesis
and genetic engineering in Gram-negative bacteria.
Can. J. Microbiol. 41 (1995) 1053-1055.
Alexeyev, M.F., Shokolenko, I.N. Mini-Tn10 transposon
derivatives for insertion mutagenesis and gene
delivery in the chromosome of gram-negative bacteria.
Gene 160 (1995) 59-62.
Alexeyev, M.F., Shokolenko, I.N. and Croughan,
T.P. Improved antibiotic resistance gene cassettes
and omega elements for Escherichia coli vector
construction and in vitro deletion/insertion mutagenesis.
Gene 160 (1995) 63-67.
Alexeyev M.F. and Shokolenko I.N. The RP4 oriT
AND RP4 oriT-R6K oriV DNA cassettes for construction
of specialized vectors. BioTechniques 19 (1995)
22.
Shokolenko, I.N. and Alexeyev, M.F. Transformation
of Klebsiella oxytoca VN13 and Escherichia coli
TG1 by freezing-thawing procedure. BioTechniques
18 (1995) 596.
Alexeyev M.F. Three kanamycin resistance gene
cassettes with different polylinkers. Bio/Techniques
18 (1995) 52-56.
Kozyrovska, N., Alexeyev, M., Kovtunovich, G.,
Gun'kovska, N., and Kordium V. Survival of Klebsiella
oxytoca VN13 engineered for bioluminescence on
barley roots during plant vegetation. Microb.
Releases 2 (1994): 261-265.
Kozyrovskaya N.A., Alexeyev M.F., Kovtunovich
G.L., Gun’kovskaya N.V., Kordjum V.A. Bioluminescence-based
detection of Klebsiella oxytoca VN13 in the environment.
Biopolymery I klitina, 1994 V.10, N2:17-23.
Romanovskaya, V.A., Alexeyev, M.F., Gunkovskaya,
N.V., Stolyar, S.M., Shatokhina, E.S., Malashenko
Yu.R. Screening for restriction endonucleases
in methane oxidizing bacteria Kurt. Microbiol.
J. 1992 V.54, N6:32-40.
Alexeyev, M.F., Gun'kovskaya, N.V., Romanovskaya,
V.A., Malashenko, Yu.R. Methylovarius whittenburyi-producer
of Mwh I, the new izoschisomer of HpaI. Ukr. Microbiol.
J. 1992 V.54, N6:70-73.
Alexeyev M.F. Cloning in the lacIq gene of pTTQ
plasmids: "reverse" colour reaction.
Biopolym.Kletka.1992 V8, N6:58-60.
19. Nguyen Van Hoa, Alexeyev Mikhail, Kozyrovskaya
Natalia, Elhai Jeffrey. Anabaena thermalis: a
nitrogen-fixing endorhizosphere cyanobacterium
associated with rice. Biopolym. Kletka. 1992 V8,
N5:44-48.
Alexeyev, M.F., Kovtunovich, G.L., Kravetz,
A.N., Solonin, A.S. pZE8 natural hsd plasmid replicon
based cloning vectors for Escherichia coli and
endorhizosphere nitrogen fixer Klebsiella oxytoca
VN13. Biopolym. Kletka.1992 V.8, N5:48-54.
Alexeyev, M.F. and Gun'kovskaya, N.V. The rapid
method for enterobacteria transformation and some
factors influencing its efficiency Biopolym. Kletka.
1992 V.8, N3:47-51.
Alexeyev, M.F. and Kozyrovskaya, N.A. Some aspects
of molecular cyanobacterial genetics. A review.
Biopolym. Kletka. 1990 V.6, N5:23-45. |
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| Presentations |
| 1. Mikhail F. Alexeyev, Studying the
Structure-Function Relationships in Membrane Proteins
with Transposable Dual Reporters. Gordon Research
Conference on Membrane Transport Proteins, London,
CT (2000)
2. Liqing Chen, Edward X. Zhou, Brian A. Halloran,
Mikhail F. Alexeyev, Nathan N. Aronson, Jr., Edward
J. Meehan. Crystal Structure of S. marcescens
Chitinase A: Active-Site Mutant W539A. American
crystallographic association annual meeting. 2002.
Invited abstract W0284
3. Alexeyev, M.F. and Winkler H.H. Survey of
Positively Charged Residues in Rickettsia prowazekii
ATP/ADP Translocase. American Society for Microbiology
100th General Meeting. Los Angeles, CA May 21-25,
2000. Abstract K-43.
4. Alexeyev, M.F. and Winkler H.H. Dual pho-lac
and lac-pho reporters for probing the topology
of integral membrane proteins: the Escherichia
coli lactose permease (LacY) and Rickettsia prowazekii
ATP/ADP translocase (Tlc). American Society for
Microbiology 98th General Meeting. Atlanta, GA
1998. Abstract K-90.
5. Alexeyev, M.F. and Winkler, H.W. Engineering
of a synthetic open reading frame with coding
capacity for a Rickettsia prowazekii ATP/ADP antiporter
protein (translocase). Thirteenth Sesqui-Annual
Meeting of the American Society for Rickettsiology.
Abstract # 37.
6. Alexeyev, M.F., Engler, D.A., Scott-Burden,
T., and Casscells, W. FGF-2 Facilitates uptake
of DNA complexes by living cells. ASBMB/ASIP/AAI
joint meeting. June 1-6, 1996. New Orleans, LA.
Late Breaking Abstracts LB124.
7. Croughan, T.P., Cao, H.X., Utomo, H.S., Alexeyev,
M.F., Chu, Q.R., Reagan, R.P., Wang, X.H., Meche,
M.M., and Trumps, D.B. Application of biotechnology
to rice improvement. Proceedings of the 25th RTWG
meeting, New Orleans, LA, March 1994. P. 62.
8. Romanovskaja, V.A., Alexeyev, M.F., Gun'kovskaya,
N.V., Malashenko, Yu.R. Restrictases of methane-oxidizing
bacteria. In Abstracts of FASEB Summer Research
Conference Restriction Endonucleases and Modification
Methyltransferases: Structure and Mechanisms".
Saxstons River, Vermont (USA), July 3-8, 1993.P.96.
9. Kozyrovskaya, N.A., Alexeyev, M.F., Gun'kovskaya,
N.V., Kovtunovich, G.L. and Kordjum, V.A. Monitoring
of the nitrogen-fixing bacteria in agrobiocenosis.
In Abstracts of VIIIth Eastern Europe Symposium
on Biological Nitrogen Fixation "Nitrogenfix-92".
Saratov, Sept. 22-26 , 1992. P.39.
10. Alexeyev, M.F., Kozyrovskaya, N.A., Makitruk,
V.L. Klebsiella oxytoca mutants defective in synthesis/excretion
of indole compounds. In Abstracts of VIIIth Eastern
Europe Symposium on Biological Nitrogen Fixation
"Nitrogenfix-92". Saratov, 22-26 Sept.,
1992 P.47.
11. Romanovskaya, V.A., Gunkovskaya, N.V., Alexeyev,
M.F. Restriction endonucleases screening in methane
oxidizing bacteria. VII Int. Symp. on Microbial
Growth on C1 compounds. Warwick. Great Britain
1992, C103.
12. Alexeyev, M.F., Gun'kovskaya, N.V., Kozyrovskaya,
N.A., Makitruk, V.L. and Ruckdashell, E. 1992.
Indoles production by plant-associated nitrogen-fixing
Klebsiella. In: Abstracts of the 6th International
Symposium on Microbial Ecology (ISME-6), Barcelona,
Sept. 6-11, 1992 p.167. |
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