Hydrogen has an extensive potential as a clean and renewable energy source. Photosynthetic, non-sulphur, purple bacteria, Rhodobacter sphaeroides O.U.001 produces molecular hydrogen by nitrogenase enzyme. Nitrogenase enzyme is encoded by nifHDK genes and expression of the structural genes, nifHDK, is controlled by NifA which is encoded by nifA gene. The transcription of nifA is under the control of Ntr system and product of prrA gene. Relationship between the genes that have roles in nitrogenase synthesis should be understood well to increase biological hydrogen production. In this work, expression levels of nitrogenase encoding nifH and control genes nifA, prrA were examined at different physiological conditions. In addition to modifications in expression levels, changes in hydrogen production and growth capacity were also investigated in response to different concentrations of ammonium source, oxygen and different light intensities. In this study, it was found that increasing concentrations of ammonium chloride caused decrease in hydrogen production. Glutamate containing medium had the capacity for higher hydrogen production. The expression levels of nifH and nifA genes decreased with the increase in concentrations of ammonium chloride. There was a negative correlation between the expression levels of prrA gene and its target, nifA gene. Hydrogen production was observed even in aerobic conditions of the same media compositions. It was observed that different culture media had changing growth and hydrogen production capabilities at different light intensities. There was no direct proportion between the expression levels of nifH gene and amount of hydrogen at different light intensities.

Phosphoglucomutase (PGM) is one of the central enzymes in energy metabolism at a branch point at the head of the metabolic pathway leading into glycogen metabolism, pentose shunt and the main glycolytic cycle, catalyzing the reversible interconversion of glucose-1-phosphate to glucose-6-phosphate. Whole year, month to month analysis of pattern of allozyme variation at Pgm and Hk loci in Apis mellifera L. from three provinces / Kirklareli, Artvin, and Hatay revealed that there is significant seasonal variation of allozyme frequencies at Pgm locus (P&lt / 0.001). The difference in genotype frequencies between summer and winter samples is apparent in Pgm, whereas at Hk locus, which is analyzed as a control there is seasonal variation in genotype frequencies. Biochemical measurements of the enzyme activities and glycogen content of different Pgm genotypes were performed to determine the effect of different Pgm genotypes on the physiological performance of the honeybees and it was observed that both enzyme activity and glycogen amount is higher in heterozygote individuals which are in high frequency during winter months (P&lt / 0.0001). Furthermore, PGM enzyme activity and glycogen content was found to be significantly correlated. These findings clearly demonstrate that biochemical differences between different Pgm genotypes have functional correlates that lead to significant variations in glycogen content of the honeybees and may have adaptive consequences.

Prostate cancer (PCa) is one of the most prevelant cancers in males in many countries, increasing in frequency with age. PCa incidence and mortality rates are not evenly distributed worldwide. Family history is an established risk factor for prostate cancer and families demonstrating autosomal dominant or X-linked transmission of susceptibility have been observed. Although an increasing number of candidate genes or hereditary prostate cancer susceptibility have been identified, only 5 to 10 percent of prostate cancer cases in the population may arise from major susceptibility genes. A few risk factors for PCa development are advanced age, an intact androgen metabolism, ethnicity, and genetic background. Other genetic factors, in combination with possible environmental risk factors for prostate cancer, may have greater public health importance. Genetic polymorphisms that may be associated with prostate cancer risk are much more common in the population than are high-penetrance cancer susceptibility genes. In this study, the effect of N-acetyltransferase 2 (NAT2) and Glutathione S-transferases (GSTM1 and GSTT1) were investigated, since polymorphism in these genes may alter their enzymatic activity and, therefore, their capacity to biotransform xenobiotic compounds. In order to evaluate the potential association between NAT2 , GSTM1 and GSTT1 genotypes and prostate cancer risk, a hospital based case control study was carried out in a Turkish population consisting of 30 histologically confirmed incident prostate cancer cases and 67 control subjects with no present or previous history of cancer. The GSTM1 and GSTT1 genotypes showed no significant differences between case and control groups, with respect to their frequencies and it was observed that GSTM1 null genotype was more common in cases with a 60% frequency. Even though the frequency of slow NAT2 acetylator genotype was 80% in cases and 50,7% in controls NAT2 rapid acetylator showed no association with prostate cancer statistically. These results suggested that GSTM1 null genotype is a susceptibility factor for prostate cancer, particularly in the presence of NAT2 slow acetylator genotype with no significance. Further studies with a larger size are required to confirm the presence and significance of this relationship.

Free radicals which have critical roles in living systems through their beneficial and detrimental effects play an important role in medical revolution in health. Radicals are produced in the cells and tissues of our bodies by various processes and reactions. Diabetes mellitus is an extremely common disease in the world which seems to be accompanied by a shortage of antioxidants and an increase in free radicals, the end result of oxidative stress. Glutathione S-Transferases (GST / EC 2.5.1.18) are found in enzymatic defense system which has a role in defending cells against potentially toxic and/or carcinogenic compounds. In this study, the changes in the activities and expressions of various GST isozymes in the liver of diabetic rats related to oxidative stress were studied. The effects of antioxidants, Vitamin C and &amp / #945 / -Lipoic acid on GST isozyme activities and mRNA expressions were also investigated. According to our results, diabetic rats exhibited decreased mRNA expressions of both GSTA2 and GSTM1 genes, but the activities of only GST Mu isozyme decreased in diabetic rats, compared to controls and GST Alpha isozyme activity remained unchanged in diabetic animals. Our results also showed that &amp / #945 / -Lipoic acid individually has no significant effect on both GSTA2 and GSTM1 gene expressions and activities. Furthermore, although the administration of Vitamin C alone showed no significant effect on all GST isozyme activities, it decreased GSTA2 mRNA expression significantly. The administration of Vitamin C and &amp / #945 / -Lipoic acid together affected both GSTA2 and GSTM1 mRNA expressions in control rats, but only GST Mu activity showed a significant change. The results of this study showed that, the administration of two antioxidants, &amp / #945 / -Lipoic acid and Vitamin C alone and together did not reverse the results of diabetes at the level of both gene expression and activities of GST isozymes.

Evolutionary models addressing interaction between genetics and morphology propose that during development, morphological traits of organisms are under canalization selection resulting in constancy in morphology through evolutionary time. The hypothesis of genetic homeostasis predict that because of developmental buffering effects of heterosis, high level heterozygosity results in low level of morphological variance from the norms of canalized shape of the population. The aim of the present study is to test whether the variation in shape of organisms is negatively correlated with genetic variation in Pseudophoxinus populations. Sample collection was performed from eight localities for four different Pseudophoxinus species (P. crassus, P. battalgili, P. egridiri, P. sp) in Central and South Anatolia in summer period of 2006. Shape variation of the specimens was determined using geometric morphometric methods. Genetic variation was based on six microsatellite and ten allozyme loci. All the microsatellite loci were found to be polymorphic. However, the percentage of monomorphic locus for allozymes varied from 90% to 60% per population. Statistically significant negative correlation was observed between shape and genetic variation derived from microsatellite data. However, this was not the case for allozyme heterozygosity / there wasn&rsquo / t any significant relationship between shape variation and allozymes heterozygosity. Low number of polymorphic loci observed in allozymes may prevent to reveal possible relationship between shape and genetic variations. As a result, the present study confirmed the hypothesis of genetic homeostasis for microsatellite data.

Chaperonins (Hsp60 chaperones) comprise a class of oligomeric, high-molecular-weight chaperones that have the unique ability to fold some proteins that cannot be folded by simpler chaperone systems. The term &ldquo / thermosome&rdquo / is used for molecular chaperonins from Archaeal organisms since they accumulate to high levels upon heat-shock. In this study first time, we have cloned and sequenced two Hsp60 subunit genes (&amp / #945 / and &amp / #946 / ) from a thermoacidophilic archaeon Thermoplasma volcanium. For cloning we have followed a PCR based strategy. Amplification of Hsp60 &amp / #945 / gene from chromosomal DNA of T. volcanium yielded a product of 1939 bp amplicon and that of Hsp60 &amp / #946 / gene yielded a product of 1921 bp amplicon. After ligation of the PCR fragments to pDrive vector, recombinant plasmids were transferred into E. coli TG-1 competent cells and recombinant colonies were selected by blue/white screening. The cloning of two subunit genes were confirmed by restriction mapping and by sequencing. Both subunit genes were then subcloned to pUC18 vector consequtively to construct a co-expression vector. Both subunit genes were expressed under control of their own promoters leading to production of active Hsp60 chaperonin (thermosome). Chaperone activity of the recombinant thermosome was shown by using pig citrate synthase enzyme as substrate. Thermosome induced refolding was observed when renaturation was carried out at 50&deg / C for 2,5 h. Under this condition, citrate synthase activities associated with control and test were &amp / #61508 / mA412/min:19.0 and &amp / #61508 / mA412/min:24.0 respectively. Clustal W Version 1.82 was used for multiple sequence alignments of Hsp60 &amp / #61537 / and Hsp60 &amp / #61538 / proteins of T. volcanium and other Hsp60 proteins from various eukaryotes, bacteria and archaea. The highest sequence similarity was found between &amp / #945 / subunit proteins of T. volcanium and T. acidophilum (94%) and &amp / #946 / subunit proteins of T. volcanium and T. acidophilum (93%). Clusters of orthologous groups and conserved domain database searches revealed the phylogenetic relationships between Hsp60 &amp / #61537 / and Hsp60 &amp / #61538 / subunits of T. volcanium thermosome and other Hsp60 proteins from various eukaryotes, bacteria and archaea. Induction of both subunit genes under heat shock (65&deg / C, 70&deg / C and 75&deg / C for 2h) and under oxidative stress (imposed by 0,008 mM, 0,01 mM, 0,02 mM, 0,03 mM and 0,05 mM H2O2) conditions was studied by Real-Time PCR technique and amplified cDNA band density analysis.

In the present study, within and among breed genetic variability in seven native Turkish sheep breeds (Akkaraman, Dagli&ccedil / , G&ouml / k&ccedil / eada, ivesi, Karayaka, Kivircik and Morkaraman) were analyzed based on 20 microsatellite loci. For the analysis, various statistical methods such as Neighbor-Net, Factorial Correspondence Analysis (FCA) and Structure were used. High level of genetic variability within the Turkish breeds was observed. Gene pools of the breeds were visualized and found that they are highly overlapping with each other. As one of the reasons of this overlap, genetic exchange between the breeds was suggested. Dagli&ccedil / , claimed to be the ancestors of first domestic sheep in Anatolia, seemed to be the most admixed one. Yet Dagli&ccedil / , despite being the most introgressed one, still might be exhibiting its uniqueness. Observations implied that conservation practices concerning Dagli&ccedil / must be urgently revised. Results of the present study do not support previous observations about the genetic differentiation patterns of the breeds within Anatolia. Possible reasons of the discrepancies between the observations were discussed. Genetically extreme individuals can be identified by Structure, Assignment and FCA tests. These methods are found to be promising in establishing new relatively pure breeds or in saving the breeds from further genetic contamination. Genetically outlier individuals were shown not to exhibit any distinct morphological differences. Unknown band patterns were found by RFLP and SSCP of mtDNA Control Region and the individuals harboring those were sequenced. They were shown to belong to the common haplogroups A, B or C. No novel haplogroup was found.

We analyzed a total of 760 worker bees, two samples per colony, 390 colonies in 26 provinces in Turkey to determine and compare the genetic variation of Turkish honey bee (Apis mellifera L.) populations using 10 primers for RAPD and 6 microsatellite loci. Mean gene diversity levels ranged from 0.035 (Sanliurfa) to 0.175 (Antalya) for RAPD and 0.449 (Mugla) to 0.739 (Artvin) for microsatellite markers. Private band patterns and alleles, pairwise FST values support that the Anatolian honey bees belong to C lineage except for Hatay and Sanliurfa populations illustrated from previous findings of mitochondrial DNA studies. Genetic differentiation (GST) from RAPD data ranged from 0.060 (Bilecik and Mugla) to 0.395 (G&ouml / k&ccedil / eada and Sanliurfa). The genetic diversity (FST) for microsatellites ranged from -0.068 (G&ouml / k&ccedil / eada and &amp / #272 / zmir) to 0.347 (Konya and Mugla). The results of the present research are in agreement to that of previous study in Turkish honey bee populations which used different microsatellite loci. That is the genetic variation was the highest in African, the lowest in European and intermediate in the Mediterranean honey bee populations. The data presented here indicate that in spite of extensive migratory beekeeping, there is still a large genetic differentiation among honey bee populations. These results should be considered in establishment of conservation plans particularly in moving of colonies between regions. The most importantly introduction of bees with foreign origin and distribution queen bees from one center to all over the country which will homogenize the gene pool of the populations should be prevented

More than half of the Pinaceae is including in genus Pinus covers the large parts of vegetation of northern hemisphere. The Anatolian Black Pine is one of the subspecies of European Black Pine, growing naturally as a widespread mid elevation species of Taurus, western Anatolian and northern Anatolian Mountains of Turkey. Although it is disputed that there are 5 varieties of Anatolian black pine but three of these are well recognized. These are Pinus nigra subsp. pallasiana var. pallasiana, Pinus nigra Arnold subsp. pallasiana var. pyramidata (pyrimidal black pine) and Pinus nigra Arnold subsp. pallasiana var. seneriana. To determine the genetic relationship between Anatolian black pine and its well recognized varieties, 3 different taxa of Anatolian black pine (well recognized varieties) were sampled in the natural range of species and non-coding trn regions of chloroplast DNA (cpDNA) were sequenced to assess the genetic structure of the species. Three sectors of trn region were examined. Analysis was assessed with using MEGA version 4.0 and Arlequin 2.000 softwares. Considering genetic diversity of three Anatolian black pine taxa with respect to trn regions and parsimonic sites, the result showed that P. nigra subsp pallasiana var seneriana was more polymorphic than other two taxa. Also, the most distant taxon that show differences in trn sequences when compared to other taxa was P. nigra subp pallasiana var pyramidata. The constructed phylogenetic tree showed that individuals of P.nigra subsp pallasiana var pyramidata were grouped together. However, other two taxa showed a dispersed allocation in the tree. This result indicates that var pyramidata was the most distant taxon. According to present study, there is no clear speciation between varieties and var pallasiana. The differences between them may be a result of mutation which may have occured in the genes coding for growth and form of Anatolian black pine.

Colorectal carcinoma (CRC) is often lethal when invasion and/or metastasis occur. 15-lipoxygenase-1 (15-LO-1), an enzyme of the inflammatory eicosanoid pathway, oxidatively metabolizes linoleic acid and its expression is repressed in CRC. In the present study, the hypothesis that the lack of 15-LO-1 expression in CRC cells may contribute to the tumorigenesis was investigated. Therefore 15-LO-1 was introduced to colon cancer cell line HT-29 that does not have detectable levels of the 15-LO-1. The HT-29 cells were transiently transfected with the eukaryotic expression vector pcDNA3.1-15-LO-1 and the effects of 15-LO-1 expression on the proliferation, apoptosis as wells as metastatic potential of the cells were investigated. Cellular proliferation was analyzed by MTT assay and the apoptotic potential of 15-LO-1 was evaluated by acridine orange, floating cell ratio and caspase-3 assays as well as expression levels of the antiapoptotic protein XIAP. Cellular migration and invasion were investigated by Boyden chamber migration and Matrigel invasion assay.The data indicates that 15-LO-1 expression significantly decreased cell proliferation and increased apoptosis. In addition, a significant reduction was observed in migratory and invasive capacity 15-LO-1 expression also significantly reduced the expression of metastasis associated 1 protein (MTA-1). Taken together we propose that 15-LO-1 expression in CRC can inhibit colon cancer cell growth through induction of apoptotic cell death and may contribute to the inhibition of metastatic capacity in vitro which may be exploited for therapeutic purposes.