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2001

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Articles 2131 - 2160 of 2477

Full-Text Articles in Life Sciences

Phylogenetic Position Of Eimeria Antrozoi, A Bat Coccidium (Apicomplexa: Eimeriidae) And Its Relationship To Morphologically Similar Eimeria Spp. From Bats And Rodents Based On Nuclear 18s And Plastid 23s Rdna Sequences, Xiaomin Zhao, Donald W. Duszynski, Eric S. Loker Jan 2001

Phylogenetic Position Of Eimeria Antrozoi, A Bat Coccidium (Apicomplexa: Eimeriidae) And Its Relationship To Morphologically Similar Eimeria Spp. From Bats And Rodents Based On Nuclear 18s And Plastid 23s Rdna Sequences, Xiaomin Zhao, Donald W. Duszynski, Eric S. Loker

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Partial plastid 23S and nuclear 18S rDNA genes were amplified and sequenced from 2 morphologically similar Eimeria species, E. antrozoi from a bat (Antrozous pallidus) and E. arizonensis from deer mice (Peromyscus spp.), as well as some other Eimeria species from bats and rodents. The phylogenetic trees clearly separated E. antrozoi from E. arizonensis. The phylogenies based on plastid 23S rDNA data and combined data of both plastid and nuclear genes grouped 2 bat Eimeria and 3 morphologically similar Eimeria species from rodents into 2 separate clades with high bootstrap support (100%, 3 rodent Eimeria species; …

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Phylogenetic Analysis Of The Rhabdocoela (Platyhelminthes) With Emphasis On The Neodermata And Relatives, David Zamparo, Daniel R. Brooks, Deborah A. Mclennan, Eric P. Hoberg Jan 2001

Phylogenetic Analysis Of The Rhabdocoela (Platyhelminthes) With Emphasis On The Neodermata And Relatives, David Zamparo, Daniel R. Brooks, Deborah A. Mclennan, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Phylogenetic systematic analysis of 24 taxa representing the rhabdocoel platyhelminths, based on a suite of 89 morphological characters, produced two equally parsimonious trees, 181 steps long, with a consistency index (CI) of 0.69 and a rescaled consistency index (RCI) of 0.56, differing only with respect to that portion of the tree containing Umagillidae, Acholadidae, Graffillinae, Pseudograffillinae, Pterastericolidae and Hypoblepharinidae. Our results accommodate all previously proposed sister taxa to the Neodermata in a single clade in which ((Dalyelliidae + Temnocephalida) Typhloplanidae) is the sister group of ((Fecampiidae + Urastoma) (Udonella ((Aspidogastrea + Digenea) (Monogenea (Gyrocotylidea (Amphilinidea + Eucestoda)))))). Bootstrap …

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The Genus Striga (Scrophulariaceae) In Africa, Kamal I. Mohamed, Lytton John Musselman, Charles R. Riches Jan 2001

The Genus Striga (Scrophulariaceae) In Africa, Kamal I. Mohamed, Lytton John Musselman, Charles R. Riches

Biological Sciences Faculty Publications

Twenty-eight species and six subspecies of the hemiparasitic genus Striga Lour., witchweed, occur in Africa. Twenty-two species are endemic. Witchweeds occur throughout the continent with greatest diversity in the grasslands and savannas north of the equator. Striga gesnerioides (Willd.) Vatke and S. hermonthica (Del.) Benth. have developed host-specific strains that may have distinct morphotypes. me accord these no formal taxonomic status. Striga hermonthica and S. asiatica (L.) Kuntze, limited to agroecosystems, may be recently derived from non-ruderal species. Striga hirsuta Benth. and S. lutea Lour., sometimes treated as conspecific with S. asiatica, are recognized as distinct species restricted …

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The 6th International Conference And Workshop On Lobster Biology And Management: An Introduction, Mark J. Butler Iv Jan 2001

The 6th International Conference And Workshop On Lobster Biology And Management: An Introduction, Mark J. Butler Iv

Biological Sciences Faculty Publications

Every three years or so, the International Conference and Workshop on Lobster Biology and Management (ICWL) brings together lobster scientists, fishery managers, and industry representatives from around the world for a week of scientific presentations, workshops, and discussions on lobster biology and management. The first ICWL was held in Perth, Australia, in January 1977. Its purpose was to bring together a small group of lobster researchers from the USA and Australia to discuss common issues and themes. That initial workshop spawned a continuing series of meetings that have become the international lobster conference for scientists—the equivalent of an international congress …

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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 …

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Tick Immunity To Microbial Infections: Control Of Representative Bacteria In The Hard Tick Dermacentor Variabilis (Acari: Ixodidae), Robert Johns, Shane Ceraul, Daniel E. Sonenshine, Wayne L. Hynes Jan 2001

Tick Immunity To Microbial Infections: Control Of Representative Bacteria In The Hard Tick Dermacentor Variabilis (Acari: Ixodidae), Robert Johns, Shane Ceraul, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

No abstract provided.

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Cellular Adhesion And Adhesion Molecules, Zerri̇n Seller Jan 2001

Cellular Adhesion And Adhesion Molecules, Zerri̇n Seller

Turkish Journal of Biology

In recent years, cell adhesion and cell adhesion molecules have been shown to be important for many normal biological processes, including embryonic cell migration, immune system functions and wound healing. It has also been shown that they contribute to the pathogenesis of a large number of common human disorders, such as rheumatoid arthritis and tumor cell metastasis in cancer. In this review, the basic mechanisms of cellular adhesion and the structural and functional features of adhesion molecules are summarized.

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Expression Of A Fungal Cellulase Gene By \Beta-Glucanase Promoter Of Streptococcus Bovis, Mehmet Sai̇t Eki̇nci̇ Jan 2001

Expression Of A Fungal Cellulase Gene By \Beta-Glucanase Promoter Of Streptococcus Bovis, Mehmet Sai̇t Eki̇nci̇

Turkish Journal of Biology

The promoter region of the §-glucanase gene was identified using a transcriptional fusion between the upstream region of the Streptococcus bovis \beta-glucanase gene and the celA gene. Using the transcriptional and protein localisation signals of the S. bovis \beta-glucanase gene, an in-frame tarnslational fusion between the end of the \beta-glucanase signal sequence and the ATG of the Neocallimastix patriciarum celA gene was constructed. The \beta-glucanase promoter-celA fusion was expressed in both E. coli and S. bovis. The activity of the protein produced was found to be cell-associated in E. coli, it but localised to the supernatant fraction of harvested cells …

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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 …

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Effect Of Some Organophosphorus Insecticides On Soil Microorganisms, Meti̇n Diğrak, Ferdağ Kazanici Jan 2001

Effect Of Some Organophosphorus Insecticides On Soil Microorganisms, Meti̇n Diğrak, Ferdağ Kazanici

Turkish Journal of Biology

The effect of some organophosphorus insecticides [Isofenphos (=Oftanol DS 40), Phorate (=Thimet 10G and Foratox 10-G) and Fonofos] were investigated on soil microbiota (total viable bacteria, actinomycetes, anaerobic bacteria, aerobic endospores, proteolytic bacteria, cellülolytic microorganisms and yeast-mold). In the isofenphos-treated soil sample, the total viable bacteria number was found to be higher than that of the control groups during incubation. Moreover, it was observed that this treatment had no inhibitory effect on the development of the other microorganism groups. It was determined that the fonofos and phorate pesticides were had no inhibitory effect on the devel- opment of the soil …

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Purification Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Meti̇n Yildirim Jan 2001

Purification Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Meti̇n Yildirim

Turkish Journal of Biology

Buchnericin LB produced by Lactobacillus buchneri LB was purified to homogeneity by a rapid and simple three-step purification procedure including freeze drying, silicic acid adsorption/desorption and cation-exchange chromatography. After the silicic acid and cation-exchange chromatography steps, the activity of buchnericin LB was recovered by 85 and 25%, and its purity increased about 111 and 2,500 fold, respectively. It was determined that the adsorption of buchnericin LB to silicic acid and cation-exchange chromatography was dependent on the pH of the suspending environment. The molecular weight of buchnericin LB was determined to be about 4.0 kDa by tricine SDS-PAGE.

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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 …

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Characterization Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Zeli̇ha Yildirim, Meti̇n Yildirim Jan 2001

Characterization Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Zeli̇ha Yildirim, Meti̇n Yildirim

Turkish Journal of Biology

Lactobacillus buchneri LB isolated from a commercially fermented vegetable product produced a bacteriocin-designated buchnericin LB. It was found that buchnericin LB was heat-stable (90-121^oC for 15 min) and hydrolyzed by proteases, \alpha-chymotrypsin, trypsin, papain, proteinase K and pepsin. However, it was observed that it was resistant to catalase, peroxidase, lipase, amylases and organic solvents. Also, it was found that it retained its biological activity after exposure to pH 2.0-9.0 and after storage at -20^o and -70^oC. It was determined that buchnericin LB had a wide inhibitory spectrum, being inhibitory to the Listeria, Bacillus, Enterococcus, Micrococcus, Lactobacillus, Leuconostoc, Pediococcus, and Streptococcus …

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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.

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

Blood Serum Proteins Of Apodemus Flavicollis And Apodemus Hermonensis (Mammalia: Rodentia) In Turkey, Reyhan Çolak, Ercüment Çolak, Nuri̇ Yi̇ği̇t, Mustafa Sözen, Şaki̇r Özkurt

Turkish Journal of Biology

The globulin, albumin, postalbumin, and prealbumin proteins of Apodemus flavicollis and Apodemus hermonensiswere examined by SDS-PAGE. In A. flavicollis and A. hermonensis respectively, 6-9 and 7-9 electrophoretic bands were determined in the globulin region, respectively. Both species have one band in the postalbumin zone, and two bands in the prealbumin zone. A. flavicollis differs from A. hermonensisin terms of postalbumin.

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Effects Of Sewage Pollution The Structure Of The Community Of Ulva Lactuca, Enteremorpha Linza And Rocky Macrofauna In Dışliman Of Sinop, Levent Bat, Mehmet Akbulut, Murat Sezgi̇n, Mehmet Çulha Jan 2001

Effects Of Sewage Pollution The Structure Of The Community Of Ulva Lactuca, Enteremorpha Linza And Rocky Macrofauna In Dışliman Of Sinop, Levent Bat, Mehmet Akbulut, Murat Sezgi̇n, Mehmet Çulha

Turkish Journal of Biology

Untreated sewage and domestic wastes from the Sinop outfall enter the Dışliman region. The effect of this on the distribution of Ulva lactuca, Enteromorpha linza and benthic macrofauna and on enviromental parameters was determined. Increases in the growth of opportunistic green algae such as Ulva lactuca and Enteromorpha linzain response to increased nutrient supply in the Dışliman coastal ecosystems in Sinop are reported in the present study. The results of this study show that organic enrichment also increases, with Mytilus galloprovincialis (Mollusca), Erichthonius brasiliensis, Echinogammarus olivii and Amphitoes ramondi, Idotea baltica and Sphaeroma serratum(Crustacea) being the most abundant species.

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Identification And Evaluation Of Clinically Significant Nocardia Brasiliensis, Nocardia Farcinica And Nocardia Otitidiscaviarum Strains Using Pyrolysis Mass Spectrometry (Pyms), Kami̇l Işik, Ergi̇n Kari̇ptaş, Nevzat Şahi̇n, Alan C. Ward, Micheal Goodfellow Jan 2001

Identification And Evaluation Of Clinically Significant Nocardia Brasiliensis, Nocardia Farcinica And Nocardia Otitidiscaviarum Strains Using Pyrolysis Mass Spectrometry (Pyms), Kami̇l Işik, Ergi̇n Kari̇ptaş, Nevzat Şahi̇n, Alan C. Ward, Micheal Goodfellow

Turkish Journal of Biology

Out of a total of thirty-nine Nocardia strains, eight species of N. brasiliensis, seventeen species of N. farcinica and fourteen species of N. otitidiscaviarum were identified using Pyrolysis mass spectrometry. N428, N477 N. brasiliensis; N669, N233 N. farcinica; and N231, N232 N. otitidiscaviarum duplicated strains were clustered in their own groups. Strains belonging to Nocardia brasiliensis, Nocardia farcinica and Nocardia otitidiscaviarum formed distinct pyrogroups corresponding to clusters defined in the numerical study. It can be concluded that PyMS provides a rapid and reproducible method of evaluating the taxonomic significance of Nocadia species.

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Physiological Studies On The Plant Cell Wall Degrading Enzymes Of The Rumen Bacterium Ruminococcus Flavefaciens, Emi̇n Özköse, Mehmet Sai̇t Eki̇nci̇, Numan Özcan Jan 2001

Physiological Studies On The Plant Cell Wall Degrading Enzymes Of The Rumen Bacterium Ruminococcus Flavefaciens, Emi̇n Özköse, Mehmet Sai̇t Eki̇nci̇, Numan Özcan

Turkish Journal of Biology

Two forms of Ruminococcus flavefaciens, the wild type and a trained culture of strain 17 were compared for their cellulose and xylan degradative ability when then were grown in ryegrass, cellobiose and xylan for different incubation times. No cell-associated corboxymethylcellulase (CMCase) activity was observed after 1-day incubation in cellobiose, as no supernatant activity was detected after 1 and 3 days incubation in xylan and 2 days incubation in cellobiose grown culture. Both CMCase and xylanase activities of trained culture were higher than those of wild type culture when they were grown in ryegrass. Wild type cultures, however, showed higher levels …

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Application Of Green Fluorescent Protein As A Marker For Selection Of Transgenic Mouse Embryos Before Implantation, Haydar Bağiş, Levent Keski̇ntepe Jan 2001

Application Of Green Fluorescent Protein As A Marker For Selection Of Transgenic Mouse Embryos Before Implantation, Haydar Bağiş, Levent Keski̇ntepe

Turkish Journal of Biology

In this study, we evaluated the application of green fluorescent protein (GFP) from the jellyfish Aequorea victoria, for efficient selection of possible transgenic and non-mosaic mouse embryos after microinjection. We injected 353 one-cell mouse zygotes with a DNA fragment carrying Gfp gene under the control of \beta-actin gene promoter. Eighty-seven per cent (307 embryos) of the injected embryos survived after microinjection. The surviving embryos were cultured for an additional day and then analysed for detection of GFP expression using a standard fluorescein isothiocyanate (FITC) filter set attached to a microscope. In this analysis, 34 % of the two-cell stage embryos …

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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 …

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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 …

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Nitric Oxide Synthase In The Skeletal Muscle And Arterioles Of Rats With Streptozotosin-Induced Diabetes Mellitus, Ci̇han Demi̇rci̇, Kadri̇ye Akgün Dar, İlhan Uyaner Jan 2001

Nitric Oxide Synthase In The Skeletal Muscle And Arterioles Of Rats With Streptozotosin-Induced Diabetes Mellitus, Ci̇han Demi̇rci̇, Kadri̇ye Akgün Dar, İlhan Uyaner

Turkish Journal of Biology

Nitric oxide synthase (NOS) that uses NADPH as a cofactor is an enzyme which produces nitric oxide (NO) from L-arginine. Endothelial-derived (eNOS), inducible (iNOS) and neuronal (nNOS) nitric oxide synthase are 3 known isoforms. Endothelial NO regulates the vascular tonus and causes the dilatation of vessels, while NOS localized in the sarcolemma of striated muscle plays a role in the regulation of muscle hemodynamics. Many authors have found differences in NO production in some pathological conditions such as diabetes mellitus (DM), hypertension and atherosclerosis. In this study, NADPH-diaphorase (NADPH-d) was histochemically employed to explore any changes in NO production associated …

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Transient Eexpression Of B-Glucuronidase Reporter Gene In Sainfoin (Onobrychis Viciifolia Scop.) Cotyledons Via Microprojectile Bombardmen, Sertaç Önde, Cengi̇z Sancak, Suzan Altinok, Melahat Bi̇rsi̇n, Murat Özgen Jan 2001

Transient Eexpression Of B-Glucuronidase Reporter Gene In Sainfoin (Onobrychis Viciifolia Scop.) Cotyledons Via Microprojectile Bombardmen, Sertaç Önde, Cengi̇z Sancak, Suzan Altinok, Melahat Bi̇rsi̇n, Murat Özgen

Turkish Journal of Biology

Transient \beta-glucuronidase reporter gene (GUS) expression was visualised in whole cotyledons of sainfoin (Onobrychis viciifolia Scop.) after microprojectile bombardment with pBI221.23 DNA. Optimum rupture disk pressure and sample plate distance were determined to be 1350 psi and 6 cm, respectively. Mean gold particle diameter of 1.0 µm and 48 h post-bombardment histochemical GUS assay was found to be superior to 1.6 µm gold particles and 120 h post-bombardment GUS assay. Microscopic analysis revealed the localisation of the gold particles predominantly in the epidermal cell layer, whereas less than 1% of the particles were localised in sub-epidermal cells, as deep as …

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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 …

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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 …

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Nucleotypic Effects In Different Genotypes Of Vicia Sativa L., Serap Çeli̇kler, Rahmi̇ Bi̇laloğlu Jan 2001

Nucleotypic Effects In Different Genotypes Of Vicia Sativa L., Serap Çeli̇kler, Rahmi̇ Bi̇laloğlu

Turkish Journal of Biology

Seven cultivar varieties of Vicia sativa L. were used. Nucleotypic effects of telophase (2C) nuclear DNA amounts on seed weight, percent mitotic index, stomatal frequency/mm^2, chlorophyll a and b content, root growth and shoot growth were determined. No correlation was observed between the DNA contents and the percent mitotic index, chlorophyll a and b content, or root growth of the cultivar varieties. However a significant correlation was observed between DNA content and the seed weight, stomatal frequency and shoot growth of the cultivar varieties.

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Comparison Of 22 Taurus Cedar (Cedrus Libani A. Rich.) Origins By Seedling Morphological Distance, Zeki̇ Yahyaoğlu, Ali̇ Demi̇rci̇, Nebi̇ Bi̇li̇r, Musa Genç Jan 2001

Comparison Of 22 Taurus Cedar (Cedrus Libani A. Rich.) Origins By Seedling Morphological Distance, Zeki̇ Yahyaoğlu, Ali̇ Demi̇rci̇, Nebi̇ Bi̇li̇r, Musa Genç

Turkish Journal of Biology

In this study, seeds were collected from 22 seed stands of Taurus cedar (Cedrus libani A. Rich.), and these seeds were sown at the Black Sea Technical University Nursery in 1995. The main morphological characteristics of 2+0 year old seedlings were measured in 1997. Values of seedling morphological distance were calculated using the Penrose formula to compare the origins in terms of morphological characteristics. According to the Penrose formula, when the values of morphological distance (P_{ij}) approach zero, the similarity between origins increases. Consequently, the most similar origins were Mugla-Arpacik and Isparta-Belcegiz2 (P_{18,22}=0.040), while the most different origins were Mersin-Aslankoy …

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Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner Jan 2001

Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner

Turkish Journal of Biology

Rainbow trout (Oncorhynchus mykiss) were fed diets containing three different concentrations of crude protein (56.3%, 51.7% and 45.8%) and digestible energy (21.3, 20.3 and 18.8 MJ/kg), and the effects of dietary protein and energy level on gastric evacuation and return of appetite times were investigated. Gastric evacuation determinations were achieved by slaughtering 8 fish every 6 hours until no residue was found in the cardiac stomach of fish. Return of appetite experiments were conducted by re-feeding groups of trout every 4 or 6 hours following the first feeding. The data obtained from each process was modelled by regression analysis and …

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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 …

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The Role Of P13-Kinase On Melanoma Cell Adhesion And Migration, Zerri̇n Seller, Ian R. Hart Jan 2001

The Role Of P13-Kinase On Melanoma Cell Adhesion And Migration, Zerri̇n Seller, Ian R. Hart

Turkish Journal of Biology

Integrins are responsible for anchoring cells to the extracellular matrix and also can initiate intracellular signal pathways. The interaction between integrins and the extracellular matrix results in activation of PKC, PTKs, p21Ras, MAPK and PI3-kinase. The \alpha4\beta1 integrins are expressed mainly on haematopoietic cells and also appear on several tumour types. The adhesion of \alpha4\beta1 to VCAM-1 is an essential step for lymphocyte extravasation during the inflammatory response. Furthermore, the interaction of \alpha4\beta1, expressed on tumour cells, with VCAM-1, might have a role in tumour cell extravasation. We examined the role of PI3-kinase activation in \alpha4\beta1-mediated melanoma cell adhesion and …

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