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Assessment Of Polymorphic Aflp Markers In Triticum Durum And Aegilops Sp., Aytül İnci̇rli̇, Hati̇ce Bi̇lgi̇ç, Mahi̇nur S. Akkaya Jan 2001

Assessment Of Polymorphic Aflp Markers In Triticum Durum And Aegilops Sp., Aytül İnci̇rli̇, Hati̇ce Bi̇lgi̇ç, Mahi̇nur S. Akkaya

Turkish Journal of Biology

Compared to other Polymerase Chain Reaction (PCR) based molecular markers, the Amplified Fragment Length Polymorphism (AFLP) marker system probably requires more technical expertise for the sequential enzymatic reaction steps. In addition, the reproducibility of the AFLP marker patterns is much more dependent on the quality and the purity of the DNA samples to be processed. The present study describes the optimization of reaction conditions and determination of the most polymorphic selective amplification primer sets in a comparison of winter and spring type Turkish durum wheat varieties. AFLP products resulted in about 100 bands, and the number of polymorphic AFLP loci …


Effects Of Photoperiod And Melatonin Infusions On Body Weight In Pinealectomized Juvenile Siberian Hamsters (Phodopus Sungorus), Bülent Gündüz, Alper Karakaş Jan 2001

Effects Of Photoperiod And Melatonin Infusions On Body Weight In Pinealectomized Juvenile Siberian Hamsters (Phodopus Sungorus), Bülent Gündüz, Alper Karakaş

Turkish Journal of Biology

We examined the effects of daily melatonin (Mel) infusions in pinealectomized prepubertal male Siberian hamsters in three different conditions. In one study we investigated the body weight maturation response to one hour daily infusions of 10 ng, 25 ng, or 50 ng of Mel in pinealectomized hamsters. Animals received, at day 15 of life, programmed subcutaneous infusions of Mel or vehicle at one of five time points (1900-2000, 2000-2100, 2100-2200, 2400-0100, and 0300-0400 hours) for 30 days. In long-day-born (16L) animals, Mel infusion right after lights off (2000-2100 hours) significantly inhibited body growth; this dose was ineffective at other times. …


The Effect Of Paraquat On The Activity Of Some Enzymes In Different Tissues Of Mice (Mus Musculus - Swiss Albino), Egemen Dere, Fi̇kri̇ye Polat Jan 2001

The Effect Of Paraquat On The Activity Of Some Enzymes In Different Tissues Of Mice (Mus Musculus - Swiss Albino), Egemen Dere, Fi̇kri̇ye Polat

Turkish Journal of Biology

The effects of the LD_{30} (20 mg.kg^{-1}) dose of paraquat, a herbicide, were investigated on creatine kinase (CK), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), lactate dehydrogenase (LDH) and gamma glutamyl transferase (GGT) activities in the liver, kidney and lung of mice after 2, 4, 8, 16, 32, 64 and 72 hours. After paraquat was given intraperitoneally to Mus musculus Swiss albino mice, the control groups were injected with physiological saline. The results were evaluated using the autoanalyzer as U/L. Even though significant increases in the liver tissue LDH and GGT, kidney tissue CK and lung tissue CK and …


Antiviral And Cytotoxic Activities Of Extracts From The Cell Cultures And Respective Parts Of Some Turkish Medicinal Plants, Atalay Sökmen Jan 2001

Antiviral And Cytotoxic Activities Of Extracts From The Cell Cultures And Respective Parts Of Some Turkish Medicinal Plants, Atalay Sökmen

Turkish Journal of Biology

Extracts from respective parts and cell cultures of some Turkish medicinal plants have been assessed for their antiviral and cytotoxic properties. None of the extracts tested showed notable activity against herpes simplex viruses (HSV-I and II), but a slight antiretroviral activity against HIV-I was determined in an extract from Hypericum capitatum cell cultures. On the other hand, according to cytotoxic activity test results against brine shrimp (Artemia salina), an activity level of LD_{50} at 34.9 µg/ml was found on the extracts of Ecbalium elaterium cell cultures.


The Cytogenetic Effects Of Sodium Metabisulfite, A Food Preservative In Root Tip Cells Of Allium Cepa L., Eyyüp Rencüzoğullari, Ahmet Kayraldiz, Hasan Basri̇ İla, Tonguz Çakmak, Mehmet Topaktaş Jan 2001

The Cytogenetic Effects Of Sodium Metabisulfite, A Food Preservative In Root Tip Cells Of Allium Cepa L., Eyyüp Rencüzoğullari, Ahmet Kayraldiz, Hasan Basri̇ İla, Tonguz Çakmak, Mehmet Topaktaş

Turkish Journal of Biology

The effects of sodium metabisulfite (SMB) on mitosis were investigated in Allium cepa L. The roots of A. cepa were treated with SMB concentrations of 7.5 mg/lt, 15 mg/lt and 30 mg/lt for 10- and 20-hour treatment periods. SMB significantly decreased the mitotic index (MI) at all concentrations and treatment periods. While the decreasing of the MI was dose-dependent at 10 hours treatment time, SMB increased the mitotic abnormalities dose dependently.


Molecular Characterization Of The Gene Encoding For The Salivaricin B Activity And Its Flanking Sequences, Osman Çataloluk Jan 2001

Molecular Characterization Of The Gene Encoding For The Salivaricin B Activity And Its Flanking Sequences, Osman Çataloluk

Turkish Journal of Biology

Lactic acid bacteria (LAB) produce many different antimicrobial proteins, some of which have potential in food preservation. The molecular analysis of bacteriocins has gained much attention and has advanced rapidly in recent years, and it became routine to analyze the way in which bacteriocins are expressed and translocated. Since they are associated with foods of plant and animal origins, the shared interest is that they can be utilized as a vector to deliver the active constituents at the target in the gastrointestinal tract after digestion and be used in therapy. In this respect, the molecular pattern of the expression and …


Pulsed-Field Gel Electrophoresis (Pfge) Technique And Its Use In Molecular Biology, Esi̇n Basim, Hüseyi̇n Basim Jan 2001

Pulsed-Field Gel Electrophoresis (Pfge) Technique And Its Use In Molecular Biology, Esi̇n Basim, Hüseyi̇n Basim

Turkish Journal of Biology

In recent years, the use of pulsed-field gel electrophoresis (PFGE) in the molecular biology area has been subject to much research. PFGE is a powerful tool for characterizing various strains at the DNA level, obtaining relevant information on genome size and constructing the physical and genetic map of the chromosome of bacteria that are poorly understood at the genetic level as well as in separating chromosomes in microorganisms, and in the long-range mapping of mammalian genes. PFGE also has advantage of examining the elongated and oriented configuration of large DNA molecules in agarose gels at finite field strengths. In this …


Callus Induction And Plant Regeneration From Mature Embryos Of Oat (Avena Sativa L.), Melahat A.Bi̇rsi̇n, Sertaç Önde, Murat Özgen Jan 2001

Callus Induction And Plant Regeneration From Mature Embryos Of Oat (Avena Sativa L.), Melahat A.Bi̇rsi̇n, Sertaç Önde, Murat Özgen

Turkish Journal of Biology

The aim of this study, which was conducted in Ankara University, Faculty of Agriculture, Department of Field Crops, biotechnology laboratory in 1998-1999, was to determine the callus induction and plant regeneration capacity of oat (Avena sativa L.). The mature embryos of 10 oat genotypes were utilised for callus induction. The statistical analysis of the results revealed that callus induction and plant regeneration capacity were dependent on the oat genotype. However, a significant relationship was not established between callus induction and regeneration capacity and, furthermore, the number of regenerated plants was determined to be directly related to the callus production capacity.


In Vitro Inhibition Of The Mycelial Growth Of Some Root Rot Fungi By Rhizobium Leguminosarum Biovar Phaseoli Isolates, İbrahi̇m Özkoç, Muhammet Hani̇fi̇ Deli̇veli̇ Jan 2001

In Vitro Inhibition Of The Mycelial Growth Of Some Root Rot Fungi By Rhizobium Leguminosarum Biovar Phaseoli Isolates, İbrahi̇m Özkoç, Muhammet Hani̇fi̇ Deli̇veli̇

Turkish Journal of Biology

In solid medium, the effects of twenty-three Rhizobium leguminosarum biovar phaseoli isolates on the mycelium development of the phytopathogenic fungi of three different genera (Fusarium oxysporum, Pythium ultimum and Rhizoctonia solani) were tested in vitro. The experiments were achieved by applying the superimpose dual culture technique. Most of the rhizobia tested inhibited the fungal development. The inhibition rates displayed differences in accordance with the bacteria and fungi isolates utilized. However, the inhibitory effect of the rhizobia occurred most on the isolates of Fusarium and Pythium species (up to 30.35% and 29.75% respectively) and least on those of Rhizoctonia species (16.03%). …


Ga3, Aba And Cytokinin Production By Lentinus Tigrinus And Laetiporus Sulphureus Fungi Cultured In The Medium Of Olive Oil Mill Waste, Bi̇rgül Özcan, S. Fati̇h Topcuoğlu Jan 2001

Ga3, Aba And Cytokinin Production By Lentinus Tigrinus And Laetiporus Sulphureus Fungi Cultured In The Medium Of Olive Oil Mill Waste, Bi̇rgül Özcan, S. Fati̇h Topcuoğlu

Turkish Journal of Biology

The levels of endogenous form of free, bound and total-gibberellic acid (GA_3), abscisic acid (ABA) and cytokinin (zeatin) in culture medium were determined. The changes in dry weight of the mycelium, dependent on the culture periods, was examined through the use of white-rot fungus Lentinus tigrinus and brown-rot fungus Laetiporus sulphureus which were cultured in the medium of olive oil mill waste in a static culture. Spectrophotometric techniques were used to determine the amounts of endogenous GA_3, ABA and zeatin. As a result, fungi used in this study showed that they synthesized GA_3, ABA and zeatin as a primary or …


The Evaluation Of Alkalitolerant-Mesophilic Streptomyces By Gas Chromatography And Pyrolysis Mass Spectrometry, Nevzat Şahi̇n, Kami̇l Işik, Ergi̇n Kari̇ptaş, Michael Goodfellow Jan 2001

The Evaluation Of Alkalitolerant-Mesophilic Streptomyces By Gas Chromatography And Pyrolysis Mass Spectrometry, Nevzat Şahi̇n, Kami̇l Işik, Ergi̇n Kari̇ptaş, Michael Goodfellow

Turkish Journal of Biology

Thirty-eight alkalitolerant-mesophilic Streptomyces, defined by Saddler in his numerical taxonomic study, were evaluated by gas chromotography and pyrolysis mass spectrometry. Group I Streptomyces sp. AK409 and group II Streptomyces sp. AK029 selected duplicated strains were clustered in their own groups. It was observed that the results of gas chromatography and pyrolysis mass spectrometry was in good congruance with the numerical taxonomic results. Therefore, it can be concluded that the different chemotaxonomic methods provide rapid and reproducible information for classifying biotechnologically significant Streptomyces strains.


Human Immunodeficiency Virus Type 1 Quasi Species That Rebound After Discontinuation Of Highly Active Antiretroviral Therapy Are Similar To The Viral Quasi Species Present Before Initiation Of Therapy, Keith A. Crandall, Hiromi Imamichi, Ven Natarajan, Min Kang Jiang, Robin L. Dewar, Steve Berg, Arunasri Gaddam, Marjorie Bosche, Julie A. Metcalf, Richard T. Davey Jr., H. Clifford Lane Jan 2001

Human Immunodeficiency Virus Type 1 Quasi Species That Rebound After Discontinuation Of Highly Active Antiretroviral Therapy Are Similar To The Viral Quasi Species Present Before Initiation Of Therapy, Keith A. Crandall, Hiromi Imamichi, Ven Natarajan, Min Kang Jiang, Robin L. Dewar, Steve Berg, Arunasri Gaddam, Marjorie Bosche, Julie A. Metcalf, Richard T. Davey Jr., H. Clifford Lane

Faculty Publications

In an effort to identify the sources of the viruses that emerge after discontinuation of therapy, analyses of human immunodeficiency virus (HIV) quasi species were done for 3 patients with sustained levels of HIV RNA of <50 copies/mL for 1-3 years. The sequences found in the rebounding plasma virus were closely related to those of the actively replicating form of viruses present before the initiation of combination therapy. All quasi species found in the rebounding plasma virus were also present in proviral DNA, cell-associated RNA in peripheral blood mononuclear cells (PBMC), and virion RNA derived from PBMC coculture during periods when plasma HIV RNA levels were <50 copies/mL. These findings suggest that the rapid resurgence of plasma viremia observed after discontinuation of therapy and the viruses cocultured from PBMC are derived from a relatively stable pool of the replicating form of virus rather than from activation of a previously latent pool.


Volume Management In San Environment, Chang-Soo Kim, Gyoung-Bae Kim, Bum-Joo Shin Jan 2001

Volume Management In San Environment, Chang-Soo Kim, Gyoung-Bae Kim, Bum-Joo Shin

Electrical and Computer Engineering Faculty Research & Creative Works

Logical volume managers have long been key components of a storage system. Their key features are creation of logical or virtual views of physical storage devices and support for various software RAID levels. These make it possible to overcome the limits to capacity, availability and performance of a physical storage device. Most logical volume managers are operated in a single system environment. They are not adequate for SAN (storage area network) environments where several hosts share and access a logical volume at the same time. Some recent logical volume managers are run in a multi-host environment. However, they cannot support …


Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes Jan 2001

Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Hemolymph from partially fed virgin Dermacentor variabilis females was collected following Borrelia burgdorferi challenge and assayed for antimicrobial activity against Bacillus subtilis and B. burgdorferi. A small inducible cationic peptide was identified by SDS-PAGE in the hemolymph of these ticks as early as 1h post challenge. Following purification by a three-step procedure involving sequential SepPak elution, reversed phase high performance liquid chromatography (RP-HPLC) and gel electrophoresis, the yield of the active peptide was approximately 0.1% of the total protein in the hemolymph plasma. The molecular weight, 4.2kDa, was determined by MALDI-TOF mass spectrometry. N-terminal sequencing by the Edman degradation …


Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend Jan 2001

Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend

Peer Reviewed Publications

The Pigeon River drains a 16,765-ha agricultural watershed in western Ottawa County, Michigan and discharges into south-central Lake Michigan. Extensive areas of wetlands in the upper watershed were drained in the 1920s, causing significantly altered hydrology characteristics by flashy discharges during storms and periods of snowmelt. We studied stream chemistry and hydrology for a four-year period between September, 1996, and October, 2000, to determine water quality status, to estimate annual nutrient exports, and to evaluate the effects of different seasonal flow types. Results of our study confirmed that the upper reaches of the Pigeon River experience chronically degraded water quality, …


Genes, Categories, And Species: The Evolutionary And Cognitive Causes Of The Species Problem, Michael Dietrich Jan 2001

Genes, Categories, And Species: The Evolutionary And Cognitive Causes Of The Species Problem, Michael Dietrich

Dartmouth Scholarship

Review of Genes, Categories, and Species: The Evolutionary and Cognitive Causes of the Species Problem by Jody Hey.


Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Karen Steidinger, Jan Landsberg, R. William Richardson, Earnest Truby, Barbara Blakesley, Paula Scott, Patricia Tester, Torstein Tengs, Patrice Mason, Stever Morton, David Seaborn, Wayne Litaker, Kimberly Reece, David Oldach, Leonard Haas, Gerardo Vasta Jan 2001

Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Karen Steidinger, Jan Landsberg, R. William Richardson, Earnest Truby, Barbara Blakesley, Paula Scott, Patricia Tester, Torstein Tengs, Patrice Mason, Stever Morton, David Seaborn, Wayne Litaker, Kimberly Reece, David Oldach, Leonard Haas, Gerardo Vasta

Biological Sciences Faculty Publications

Dinoflagellates can be classified both botanically and zoologically; however, they are typically put in the botanical division Pyrrhophyta. As a group they appear most related to the protistan ciliates and apicomplexans at the ultrastructure level. Within the Pyrrhophyta are both unarmored and armored forms of the dominant, motile flagellated stage. Unarmored dinoflagellates do not have thecal or wall plates arranged in specific series, whereas armored species have plates that vary in thickness but are specific in number and arrangement. In armored dinoflagellates, the plate pattern and tabulation is a diagnostic character at the family, subfamily, and even genus levels. In …


Contrasts In Tick Innate Immune Responses To Borrelia Burgdorferi Challenge: Immuno-Tolerance In Ixodes Scapularis Versus Immunocompetence In Dermacentor Variabilis (Acari: Ixodidae)., Robert Johns, Jun Ohnishi, Anne Broadwater, Daniel E. Sonenshine, Aravinda M. Desilva, Wayne L. Hynes Jan 2001

Contrasts In Tick Innate Immune Responses To Borrelia Burgdorferi Challenge: Immuno-Tolerance In Ixodes Scapularis Versus Immunocompetence In Dermacentor Variabilis (Acari: Ixodidae)., Robert Johns, Jun Ohnishi, Anne Broadwater, Daniel E. Sonenshine, Aravinda M. Desilva, Wayne L. Hynes

Biological Sciences Faculty Publications

The blacklegged tick, Ixodes scapularis Say, transmits the Lyme disease spirochete (Borrelia burgdorferi), whereas the American dog tick, Dermacentor variabilis (Say), is unable to transmit the bacterium. We compared the innate immune response of these ticks against spirochetes directly inoculated into the hemocoel cavity of ticks. In I. scapularis, some Borrelia were found associated with hemocytes, while numerous other spiral-shaped, intact bacteria remained free in the hemolymph. In contrast, in D. variabilis only remnants of the bacteria were evident in the hemolymph, indicating lysis; intact spirochetes were rare. Spirochetes were observed bound to or within the organs …


Effects Of Isochronal Exogenously Applied Synthetic-Ga_3, Fungal-Gibberellic Acid And Red Light On The Sheath Length Of The Second Leaf Of Oryza Sativa L.Cv. Tan-Ginbozu, Ş. Fati̇h Topçuoğlu, Serpi̇l Ünyayar Jan 2001

Effects Of Isochronal Exogenously Applied Synthetic-Ga_3, Fungal-Gibberellic Acid And Red Light On The Sheath Length Of The Second Leaf Of Oryza Sativa L.Cv. Tan-Ginbozu, Ş. Fati̇h Topçuoğlu, Serpi̇l Ünyayar

Turkish Journal of Biology

The effects of isochronal exogenously applied synthetic-GA_3, fungal-gibberellic acid and different light on the sheath length of the second leaf of Oryza sativa L.cv.Tan-ginbozu were determined under controlled environmental conditions. Our results showed that the effect of fungal-gibberellic acid on the sheath length of the second leaf is higher than that on the control groups (group of 1/2N Hoagland culture solution and group of 1/2N Hoagland culture solution+methanol); however, synthetic-GA_3 was more effective on the length of the second leaf than fungal gibberellic acid. Moreover, it was identified that the effect of red light is higher than that of fluorescent …


Dechlorination Of Bleached Kraft Pulp By Laccase Enzyme Produced From Some White-Rot Fungi, Nazi̇f Kolankaya, Arzu Taşpinar Ünal Jan 2001

Dechlorination Of Bleached Kraft Pulp By Laccase Enzyme Produced From Some White-Rot Fungi, Nazi̇f Kolankaya, Arzu Taşpinar Ünal

Turkish Journal of Biology

The possibility of using crude laccase in the dechlorination of chlorine-based bleached kraft pulp was investigated. Culture supernatants of seven white-rot fungal strains and kraft-pulp samples taken from E1 (Alkaline Extraction-1), E2 (Alkaline Extraction-2) and D2 (Chlorinedioxide treatment) stages of chlorine-based bleaching processes were used as the laccase source and substrates respectively during the studies. The dechlorination activity of Trametes versicolor was found to be more than that of the other fungi examined. The addition of a laccase inducer, xylidine, into the culture medium of T. Versicolor led to an increase in dechlorination activity. In the experiment performed to find …


Blood-Serum Proteins Of Rattus Rattus And Rattus Norvegicus (Mammalia: Rodentia) In Turkey, Nuri̇ Yi̇ği̇t, Reyhan Çolak, Ercüment Çolak, Mustafa Sözen, Şaki̇r Özkurt Jan 2001

Blood-Serum Proteins Of Rattus Rattus And Rattus Norvegicus (Mammalia: Rodentia) In Turkey, Nuri̇ Yi̇ği̇t, Reyhan Çolak, Ercüment Çolak, Mustafa Sözen, Şaki̇r Özkurt

Turkish Journal of Biology

The blood serum proteins of 35 live specimens of Rattus rattus and Rattus norvegicus collected from ten localities in Turkey were examined by SDS-PAGE (sodium dodecyl sulphate - polyacrylamide gel electrophoresis). Globulin, albumin, postalbumin, and prealbumin proteins in blood serum showed different electrophoretic patterns in populations of R. rattusand R. norvegicus.Because of the variations in electrophoretic patterns of both species, these patterns do not seem to be diagnostic characters in distinguishing R. rattus from R. norvegicus.


Isolation And Characterization Of Pediocin Producing Pediococcus Pentosaceus Pep1 From Vacuum-Packed Sausages, Özlem Osmanağaoğlu, Yavuz Beyatli, Ufuk Gündüz Jan 2001

Isolation And Characterization Of Pediocin Producing Pediococcus Pentosaceus Pep1 From Vacuum-Packed Sausages, Özlem Osmanağaoğlu, Yavuz Beyatli, Ufuk Gündüz

Turkish Journal of Biology

Pediococcus pentosaceus Pep1 was isolated from vacuum-packed sausages, and it was shown to produce a potentially novel antimicrobial agent active against several species of Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, Staphylococcus, Enterococcus, Bacillus and Listeria, many of which are associated with food spoilage and health hazards of food origin. Gram-negative organisms such as Yersinia enterocolitica and Escherichia coli were not inhibited by this antimicrobial agent. Since the antimicrobial agent was found to be sensitive to proteolytic enzymes, resistant to heat and organic solvents and active over a wide range of pH values, between 3 and 8, apparently most stable in the lower …


Optimization Of Pcr Amplification Of Wheat Simple Sequence Repeat Dna Markers, Nurdan Doğrar, Mahi̇nur S. Akkaya Jan 2001

Optimization Of Pcr Amplification Of Wheat Simple Sequence Repeat Dna Markers, Nurdan Doğrar, Mahi̇nur S. Akkaya

Turkish Journal of Biology

Simple Sequence Repeat (SSR) DNA markers or Microsatellites are di-, tri-, tetra-nucleotide tandem repeats containing loci of eukaryotic genomes. It is demonstrated that these loci are very polymorphic due to the change in the number of repeating units among the individuals of populations. Each SSR locus can easily be amplified by using a polymerase chain reaction (PCR) knowing the DNA sequence flanking the repeat region specifically. The only limiting feature of the application of these markers is the need for prior sequence information for developing primers in locus-specific PCR amplification. This limitation is alleviated for the economically important species and …


Substitution Of The Conserved Cysteine With Glycine (Cys82gly) Of Agmenellum Quadruplicatum Methylase Aqul (M. Aqul) Is Not Cytotoxic To E. Coli, Hati̇ce Pinarbaşi, Ergün Pinarbaşi, David P. Hornby Jan 2001

Substitution Of The Conserved Cysteine With Glycine (Cys82gly) Of Agmenellum Quadruplicatum Methylase Aqul (M. Aqul) Is Not Cytotoxic To E. Coli, Hati̇ce Pinarbaşi, Ergün Pinarbaşi, David P. Hornby

Turkish Journal of Biology

Cytosine 5 DNA methyltransferases share ten conserved motifs. Motif IV contains an absolutely conserved proline-cysteine dipeptide. The cysteine residue of this motif is involved in catalysis by forming a covalent bond with the 6-position of cytosine prior to methyl group transfer. AquI DNA methyltransferase recognising the sequence CCCGGG is a heterodimer unlike other C5 DNA methyltransferases. We changed the conserved cysteine (Cys82) of M.AquI to serine and glycine. The presence of mutations was confirmed by automated DNA sequencing. Mutants were tested by in vivo plasmid protection assay and also by transformation into mcrA+BC+ strain of E. coli. Replacement of the …


Random Amplified Polymorphic Dna (Rapd) Markers, Fevzi̇ Bardakci Jan 2001

Random Amplified Polymorphic Dna (Rapd) Markers, Fevzi̇ Bardakci

Turkish Journal of Biology

Due to advances in molecular biology techniques, large numbers of highly informative DNA markers have been developed for the identification of genetic polymorphism. In the last decade, the random amplified polymorphic DNA (RAPD) technique based on the polymerase chain reaction (PCR) has been one of the most commonly used molecular techniques to develop DNA markers. RAPD markers are amplification products of anonymous DNA sequences using single, short and arbitrary oligonucleotide primers, and thus do not require prior knowledge of a DNA sequence. Low expense, efficiency in developinga large number of DNA markers in a short time and requirement for less …


Determination Of The Dna And Amino Acid Sequences Of The Lactate Dehydrogenase Gene From Plasmodium Falciparum Strains K1 And Pf Fcbr: A Route To The Design Of New Antimalarials, Di̇lek Turgut Balik, J. John Holbrook Jan 2001

Determination Of The Dna And Amino Acid Sequences Of The Lactate Dehydrogenase Gene From Plasmodium Falciparum Strains K1 And Pf Fcbr: A Route To The Design Of New Antimalarials, Di̇lek Turgut Balik, J. John Holbrook

Turkish Journal of Biology

This paper describes cloning of the gene coding for the lactate dehydrogenase (LDH) gene from the two different strains of Plasmodium falciparum, K1 and PF FCBR. The DNA sequences of LDH genes of these two strains were found to be identical. Amino acid sequence alignment of LDH from P. falciparum strains K1 and PF FCBR (PfLDH) to some other known LDH sequences showed that PfLDH has 29% residue identities with Bacillus stearothermophilus (BsLDH) and 29%, 31%, 33% with dogfish, man-M_4, and pig-M_4 LDHs, respectively. It was also shown that PfLDH has insertions and single amino acid deletions. Two deletions are …


The Analysis Of Rhodococcus Ruber In Different Growth Conditions Using Pyrolysis Mass Spectrometry (Pyms), Ergi̇n Kari̇ptaş, Kami̇l Işik, Nevzat Şahi̇n, Reşi̇t Özkanca, Alan C. Ward Jan 2001

The Analysis Of Rhodococcus Ruber In Different Growth Conditions Using Pyrolysis Mass Spectrometry (Pyms), Ergi̇n Kari̇ptaş, Kami̇l Işik, Nevzat Şahi̇n, Reşi̇t Özkanca, Alan C. Ward

Turkish Journal of Biology

Batch grown cultures of Rhodococcus ruber from different growth phases and continuous grown cultures from carbon, phosphate and magnesium limitation were analysed by pyrolyis mass spectrometry (PyMS). Batch grown cells showed significantly different pyrograms and the stationary phase cells could be clearly distinguished from exponential phase cells. Mass pyrograms of carbon, phosphate and magnesium limited cells were clearly different and, for carbon and phosphate limitation, clear trends were seen with different dilution rates. Changes in pH and temperature had no systematic effect on mass pyrograms.


Oxylipin Pathway In The Biosynthesis Of Fresh Tomato Volatiles, Emi̇n Yilmaz Jan 2001

Oxylipin Pathway In The Biosynthesis Of Fresh Tomato Volatiles, Emi̇n Yilmaz

Turkish Journal of Biology

Fresh tomato volatiles are formed in intact fruit during ripening and upon tissue disruption. There are different pathways involved in the biosynthesis of these volatiles. The oxylipin pathway uses free unsaturated fatty acids with the sequential action of lipoxygenase, hydroperoxide lyase and alcohol dehydrogenase to produce volatile aldehyde and alcohol compounds. Oxylipin volatiles are the most important components in fresh tomato aroma. In order to genetically improve the quality of tomato aroma, the biochemistry of aroma synthesis must be studied thoroughly. This review examines current knowledge of the subject and opens new areas for further investigation.


Production Of Single-Cell Protein From Ram Horn Hydrolysate, Esabi̇ Başaran Kurbanoğlu Jan 2001

Production Of Single-Cell Protein From Ram Horn Hydrolysate, Esabi̇ Başaran Kurbanoğlu

Turkish Journal of Biology

Candida utilis NRRL Y-900 was grown on horn hydrolysate for single-cell protein production. First, ram horns obtained from slaughterhouse in Erzurum were hydrolyzed by physical and chemical methods and crude horn hydrolysate (CHH) was obtained. The contents of protein, nitrogen, ash, some minerals, total sugars and amino acids of CHH were determined and it was seen that it has sufficient organic and inorganic materials to allow its use as a substrate source in the production of single-cell protein. The CHH was enriched by addition of yeast extract, glucose and KH_2PO_4. The effects of different CHH concentrations (1, 2, 3, 4, …


In Situ Localization Of Germin Gene Expression During Auxin Induced Callus Formation, Mahmut Çalişkan Jan 2001

In Situ Localization Of Germin Gene Expression During Auxin Induced Callus Formation, Mahmut Çalişkan

Turkish Journal of Biology

Wheat embryogenic callus was induced by treating immature wheat embryos with 2,4-D. Digoxigenin-labeled germin sense and anti-sense RNA probes were prepared by in vitro transcription. By using these probes it was revealed that there was a striking induction of germin gene expression prior to visible callus formation. Although no germin gene expression was localized on the sections of immature embryos which were not incubated in callus induction medium, following 4 hours incubation in callus induction medium, germin mRNA was localized on the sections of immature embryos. Germin gene expression more conspicuous and widespread on the sections which were incubated for …