Tamás KovácsEnviroinvest · Biotechnology, Nanophage Therapy Center
Tamás Kovács
PhD
About
64
Publications
17,112
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971
Citations
Introduction
Additional affiliations
October 1993 - July 1994
September 2010 - present
Enviroinvest
Position
- Deputy CEO, Head of Nanophage Therapy Center
October 2002 - September 2010
Enviroinvest Kft.
Position
- Environmental biotechnology, bacteriophage therapy
Publications
Publications (64)
This study aimed to unveil the genetic diversity among 47 bacterial isolates from various species using start codon targeted (SCoT) markers. Six SCoT primers yielded 219 reproducible bands, with 89.04% exhibiting polymorphism. The amplification process generated 28 to 50 fragments per primer, with an average of 36.50. Genetic diversity was quantifi...
Xanthomonas arboricola pv. juglandis (Xaj) associated with walnut blight, the most significant aboveground bacterial disease causing tremendous loss worldwide. Prospective orchards between 2021 and 2022 in Hungary and Romania showed that the disease continues to spread geographically and affects several cultivars: Juglans regia ‘Sebeshelyi gömböly'...
Klebsiella pneumoniae is a nosocomial pathogen. Among its virulence factors is the capsule with a prominent role in defense and biofilm formation. Bacteriophages (phages) can evoke the lysis of bacterial cells. Due to the mode of action of their polysaccharide depolymerase enzymes, phages are typically specific for one bacterial strain and its caps...
Klebsiella pneumoniae is an opportunistic pathogen that frequently causes nosocomial and community-acquired (CA) infections. Until now, a limited number of studies has been focused on the analyses of changes affecting the virulence attributes. Genotypic and phenotypic methods were used to characterise the 39 clinical K. pneumoniae isolates; all bel...
The increasing ineffectiveness of traditional antibiotics and the rise of multidrug resistant (MDR) bacteria have necessitated the revival of bacteriophage (phage) therapy. However, bacteria might also evolve resistance against phages. Phages and their bacterial hosts coexist in nature, resulting in a continuous coevolutionary competition for survi...
Xanthomonads, members of the family Xanthomonadaceae, are economically important plant pathogenic bacteria responsible for infections of over 400 plant species. Bacteriophage-based biopesticides can provide an environmentally friendly, effective solution to control these bacteria. Bacteriophage-based biocontrol has important advantages over chemica...
Klebsiella pneumoniae is among the leading bacteria that cause nosocomial infections. The capsule of this Gram-negative bacterium is a dominant virulence factor, with a prominent role in defense and biofilm formation. Bacteriophages, which are specific for one bacterial strain and its capsule type, can evoke the lysis of bacterial cells, aided by p...
Methicillin-resistant Staphylococcus aureus (MRSA) can cause a wide range of infections from mild to life-threatening conditions. Its enhanced antibiotic resistance often leads to therapeutic failures and therefore alternative eradication methods must be considered. Potential candidates to control MRSA infections are bacteriophages and their lytic...
The accumulation of petroleum hydrocarbons in the environment substantially endangers terrestrial and aquatic ecosystems. Many microbial strains have been recognized to utilize aliphatic and aromatic hydrocarbons under aerobic conditions. Nevertheless, most of these pollutants are transferred by natural processes, including rain, into the undergrou...
Erwinia rhapontici is an opportunistic bacterial plant pathogen which can cause two types of symptoms, i.e., pink seed or crown, soft, bulb, and blossom rot (Huang et al. 2003). It has been shown to cause disease in numerous plant species including kiwifruit (Wang et al. 2017), wheat, onion, cereal, pea, bean, rye, hyacinth, and tomato (Huang et al...
Metagenomics is a helpful tool for the analysis of unculturable organisms and viruses. Viruses that target bacteria and archaea play important roles in the microbial diversity of various ecosystems. Here we show that Methanosarcina virus MV (MetMV), the second Methanosarcina sp. virus with a completely determined genome, is characteristic of hydroc...
There are still major gaps in our understanding of the bacterial factors that influencethe outcomes of humanCampylobacter jejuniinfection. The aim of this study was to compare thevirulence-associated features of 192 humanC. jejunistrains isolated from hospitalized patients withdiarrhoea (150/192, 78.1%), bloody diarrhoea (23/192, 11.9%), gastroente...
There are still major gaps in our understanding of the bacterial factors that influence the outcomes of human Campylobacter jejuni infection. The aim of this study was to compare the virulence-associated features of 192 human C. jejuni strains isolated from hospitalized patients with diarrhoea (150/192, 78.1%), bloody diarrhoea (23/192, 11.9%), gas...
The increasing incidence of carbapenemase-producing K. pneumoniae strains (CP-Kps) in the last decade has become a serious global healthcare problem. Therapeutic options for the treatment of emerging hospital clones have drastically narrowed and therefore novel approaches must be considered. Here we have isolated and characterized a lytic bacteriop...
Environmental biotechnology offers several promising techniques for the rehabilitation of polluted environments. The modern industrialized world presents novel challenges to the environmental sciences, requiring a constant development and deepening of knowledge to enable the characterization of novel pollutants and a better understanding of the bio...
The study overviews results of bacterial incidence in in vitro plant tissue cultures obtained from commercial laboratory dealing with plants micropropagation. For the exploration, the 454 pyrosequencing of the 16S rRNA gene was used. Three samples of plant in vitro cultures with visual bacterial contamination were subjected for identification of pr...
Xanthomonas oryzae pv. oryzae is the causative agent of bacterial leaf blight of rice. The application of bacteriophages may provide an effective tool against this bacterium. Here, we report the complete genome sequences of 10 newly isolated OP2-like X. oryzae pv. oryzae bacteriophages.
Campylobacter jejuni is one of the most common food-borne bacteria that causes gastrointestinal symptoms. In the present study we have investigated the molecular basis of the anti- Campylobacter effect of peppermint essential oil (PEO), one of the oldest EO used to treat gastrointestinal diseases. Transcriptomic, quantitative reverse transcription-...
Escherichia (E.) coli K1 strains remain common causative agents of neonatal sepsis and meningitis. We have isolated a lytic bacteriophage (ΦIK1) against E. coli strain IHE3034 and tested its specificity in vitro , as well as distribution and protective efficacy in vivo . The phage was shown to be specific to the K1 capsular polysaccharide. In the l...
Supplementary figure 1: concentration-dependent sensitivity of the BALB/c (A) and CD1 (B) mice for the IHE3034 E. coli K1 meningitis strain on a time scale. Ten-ten mice were intravenously injected with 100 μL doses of OD600=0.5 (~1 x 108 CFU mL−1); OD600=1 (~2 x 108 CFU mL−1); OD600=5 (~1 x 109 CFU mL−1); and OD600=10 (~2 x 109 CFU mL−1) bacterial...
Although vanA carrying Enterococcus faecium human clinical isolates have been rarely found in Hungary before 2012, they have been detected in continuously increasing numbers since then. To identify factors associated with their dissemination, we investigated the clonal relatedness and plasmids of 30 vanA carrying E. faecium isolates originating fro...
Asymptomatic bacterial colonization of the urinary bladder (asymptomatic bacteriuria, ABU) can prevent bladder colonization by uropathogens and thus symptomatic urinary tract infection (UTI). Deliberate bladder colonization with Escherichia coli ABU isolate 83972 has been shown to outcompete uropathogens and prevent symptomatic UTI by bacterial int...
Phenotypic traits of nine ABU isolates. (A) Hemolysin production on Columbia blood agar. (B) Siderophore production on CAS agar. (C) Bacteriocin production tested with different indicator strains, i.e. E. coli DH5α, UPEC 536, ABU isolate 83972. (D) Expression of rdar morphotype, i.e. simultaneous expression of curli fimbria and cellulose on Congo R...
Presence or absence of 616 ExPEC virulence/fitness-associated gene products in the ABU and model UPEC strains.
Principal Coordinates Analysis (PCoA) to examine the grouping of E. coli ABU isolates according to the presence/absence of fitness- and virulence-associated genes and their competitiveness in urine. The axes are scaled with eigenvalue scaling using the square root of the eigenvalue and indicate the percentage of variation explained in the PCoA. Str...
Characteristics of the patients.
Strain- and group-specific virulence/fitness-associated factors detected in group 1 or 2 ABU strains with increased competitiveness to E. coli 83972 and/or UPEC strain 536.
Strain- and group-specific genes detected in group 1 or 2 ABU strains with increased competitiveness to E. coli 83972 and/or UPEC strain 536.
Competitive growth experiments between nine E. coli ABU isolates and ABU model isolate E. coli 83972 in pooled human urine. The results of competitive growth experiments (mixed cultures, 1:1) between the ABU isolates and ABU model strain 83972 after 24 h of growth in pooled human urine are indicated. Asterisks indicate significantly different compe...
Heatmap indicating the presence or absence of ExPEC virulence- and fitness-associated factors including gene names/locus tags. Each row of the binary matrix indicates the presence or absence of a virulence/fitness-associated gene product (a BLASTP+ hit). Virulence/fitness factor classes are indicated at the side in black and grey. Strain names and...
Bacterial strains used in this study.
Escherichia coli can colonize the urinary bladder without causing a disease response in the host. This asymptomatic bacteriuria (ABU) can protect against recurrent symptomatic urinary tract infection by virulent bacteria. Here, we report the whole-genome sequences of nine E. coli ABU isolates from diabetic patients.
Petroleum hydrocarbons and derivatives are widespread contaminants in both aquifers and soil, their elimination is in the primary focus of environmental studies. Microorganisms are key components in biological removal of pollutants. Strains capable to utilize hydrocarbons usually appear at the contaminated sites, but their metabolic activities are...
A small-scale experimental jar system was tested in order to evaluate its ability to extend the shelf life of raw meats in households. Five different gas compositions 25%CO2 + 75%N2, 50%CO2 + 50%N2, 75%N2 + 25%O2, 25%CO2 + 50%N2 + 25%O2, 20%CO2 + 80%N2 and four different raw meats were used in the study. Changes in microbial count, texture and sens...
The appearance of somaclonal variability induced by in vitro cultivation is relatively frequent and can, in some cases, provide a valuable source of new genetic variation for crop improvement. The cause of this phenomenon remains unknown; however, there are a number of reports suggesting that epigenetics, including DNA methylations, are an importan...
Recent progress in microbial fuel cell (MFC) technology has highlighted the potential of these devices to be used as biosensors. The advantages of MFC-based biosensors are that they are phenotypic and can function in either assay- or flow-through formats. These features make them appropriate for contiguous on-line monitoring in laboratories and for...
Walnut blight caused by Xanthomonas arboricola pv. juglandis (Xaj) is one of the most frequent infective diseases of walnut, resulting in serious economic losses. One potential solution to control this disease could be the application of bacteriophages. In this study, 24 phages were isolated from soil and walnut aerial tissues infected with Xaj. Tw...
Since ancient times, silver and its compounds have been known to have a broad spectrum of antimicrobial activities for bacteria, fungi, and viruses. Due to the increasing bacterial resistance to classic antibiotics, the investigations of Ag NPs have increased. Herein, we present the preparation of ligand-free Ag NPs with 3 and 20 nm sizes by applyi...
Beta-lactam antibiotics comprise the largest group of antibacterial agents. Due to their bactericidal properties and limited toxicity to humans they are preferred in antimicrobial therapy. In most cases, therapy is empiric since susceptibility testing in diagnostic laboratories takes a relatively long time. This paper presents a novel platform that...
Bacteriophages are specific infective agents of various bacteria. They can be divided into various groups according to their life cycle. The lytic phages kill their host cells and this property can be applied for selective elimination of pathogenic bacteria. The first bacteriophage treatment was described one hundred years ago, and phage therapy ha...
The enterobacterium Erwinia amylovora is the causal agent of fire blight. This study presents the analysis of the complete genome of phage PhiEaH1, isolated from the soil surrounding an E. amylovora-infected apple tree in Hungary. Its genome is 218 kb in size, containing 244 ORFs. PhiEaH1 is the second E. amylovora infecting phage from the Siphovir...
Bacteriophages were first discovered in 1915 and used as antimicrobial tools since 1919.
However, the appearance of antibiotics confined their applications. Nevertheless, phage
therapy entered into its renaissance in the last few years as a consequence of frequent
emergence of multidrug resistance in pathogenic microbes. The developments of newer a...
The emergence of the multi-drug-resistant Staphylococcus aureus strains has prompted interest in alternatives to conventional drugs. Among the possible options one of the most promising is the therapeutic use of bacteriophages. Over the recent decades, increasing amount of literature has validated the use of bacteriophages for therapy and prophylax...
Nanocrystalline TiO2(B) and bi-crystalline (anatase-TiO2(B)) photocatalysts were prepared through hydrothermal synthesis by using different Ti-precursors such as titanium(IV) isopropoxide, titanium(IV) chloride and Degussa P25 TiO2. The obtained TiO2 samples were characterized by means of X-ray diffraction, X-ray photoelectron spectroscopy, transmi...
Erwinia amylovora is the causative agent of fire blight, a serious disease of some Rosaceae plants. The newly isolated bacteriophage PhiEaH2 is able to lyse E. amylovora in the laboratory and has reduced the occurrence of fire blight cases in field experiments. This study presents the sequenced
complete genome and analysis of phage PhiEaH2.
The changes of cell surface hydrophilicity in Bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, pH-shock, phosphate- and carbon-limitation. Although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions. An observe...
The expression of the sigB gene of Bacillus subtilis was analysed in response to a mild acid shock. This gene is subject to sigmaB-dependent regulation. It has been found that the expression of sigB is induced as part of the acid-tolerant response. In that respect sigB is similar to the previously described gene gsiB which is also a member of the s...
Questions
Questions (4)
I uploaded shotgun metagenomes and it detedted amplicons as sequence type: " We think this is an amplicon metagenome of assembled reads. " I cannot find any option to change this as an shotgun metagenome and the analysis pipleine is different, Thank you for your help.
I am not very familiar on this field and I would thank any suggestion. Our task is to isolate mRNA from hepatocytes (not from cell culture but from mice liver). We need to inhibit transcription meanwhile performing a cold trypsin digestion for 18 hours. I would be very grateful if you could suggest me a protocol how to inhibit transcription during the trypsin digestion. (The mRNA pool will be stabilized by the cold temperature (+4 oC) for this 18 hours.)
Hi, We would like to use the DNA for PCR and sequencing, but from the polluted soil and water samples the quality of DNA does not enable a successful PCR due to the inhibitors. (The quality of DNA originating from control samples - not containing hydrocarbon pollutants in a high concentration- is good for PCR). I would appreciate any suggestions in this issue.
A patient died from an unknown reason, and the doctors suspected that the causative agent was a virus. However, the determination of the virus was not successful. Because we are an NGS laboratory, we were asked to determine it with DNA sequencing. Unfortunately, if we do not enrich the viral DNA, we will detect the human DNA mostly. It would be like searching a haystack for the needle. Could anyone recommend me an enrichment strategy (either on nucleic acid or at the whole virus level)? Of course, I know also other reasons why this task can be hardly solved, but the first point would be the enrichment.
