Properties Of Deoxyribonucleic Acid Research Articles

Expounding Transport Properties of Deoxyribonucleic Acid for Electronic Applications

The scientific interest in field of molecular electronics has raised many folds in last decade to become the centre stage of contemporary research. The community of researchers working in this domain has been continuously exploring newer molecules, which can replace semiconductors of last century and still continue with the same growth. In this research communiqué, we have implemented molecular junctions using NEGF-EHT approach to elucidate the electronic transport properties of two important strands Adenine and Cytosine of Deoxyribonucleic Acid (DNA) sandwiched between with two Au leads under finite bias conditions. Important revelation include non-linear behaviour exhibited with exponential current rise around zero bias due to kondo assisted resonant tunnelling and temperature invariance over a large range of temperature. G–V graph divulges that conductance of the adenine decrease linearly with the increase in bias voltage initially and then becomes dormant for further increase in bias voltage. Contrary to this, the conductance of cytosine is observed to be equal to quantum of conductance (G0) that unambiguously indicates the metallic behaviour of cytosine. The vital information collected through this research work provides vital insight for developing applications as sensors, switches and memory devices.

FPGA Based Data Hiding Methods using DNA Cryptography Techniques

<p>To convey the information safely DNA grouping mechanisms are used. There are many methods used by DNA sequences. The proposed method is of both encryption and information concealing utilizing a few properties of Deoxyribonucleic Acid (DNA) groupings. This technique is highlighted that DNA groupings have many more intriguing properties which are used for concealing the information. There are three strategies in this encryption strategy: the Insertion Technique, the Complimentary Pair Technique and the Substitution Strategy .For every single strategy, a specific reference DNA grouping P is chosen and then the taken sequence is changed over with the mystery message M and is consolidated, so that P0 is acquired. P0 is then sent to the collector and the beneficiary can recognize and separate the message M covered up in P. This technique is proposed to utilize INSERTION Strategy. Subsequently, the proposed plan comprises for the most part of two stages. In the principal stage, the mystery information is encoded utilizing a DNA Sequence. In the second stage the encoded information is steganographically covered up into some reference DNA grouping utilizing an insertion strategy. The effectiveness of this security algorithm is seen with many merits and limitations. A, C, G, and T are the 4 nucleotides which are taken for this project.</p>

Self-Organizing Hidden Markov Model Map (SOHMMM)

A hybrid approach combining the Self-Organizing Map (SOM) and the Hidden Markov Model (HMM) is presented. The Self-Organizing Hidden Markov Model Map (SOHMMM) establishes a cross-section between the theoretic foundations and algorithmic realizations of its constituents. The respective architectures and learning methodologies are fused in an attempt to meet the increasing requirements imposed by the properties of deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein chain molecules. The fusion and synergy of the SOM unsupervised training and the HMM dynamic programming algorithms bring forth a novel on-line gradient descent unsupervised learning algorithm, which is fully integrated into the SOHMMM. Since the SOHMMM carries out probabilistic sequence analysis with little or no prior knowledge, it can have a variety of applications in clustering, dimensionality reduction and visualization of large-scale sequence spaces, and also, in sequence discrimination, search and classification. Two series of experiments based on artificial sequence data and splice junction gene sequences demonstrate the SOHMMM’s characteristics and capabilities.

DNA-Based Data Encryption and Hiding Using Playfair and Insertion Techniques

In this paper, we propose a novel algorithm to communicate data securely. The proposed technique is a composition of both encryption and data hiding using some properties of Deoxyribonucleic Acid (DNA) sequences. Hence, the proposed scheme consists mainly of two phases. In the first phase, the secret data is encrypted using a DNA and Amino Acids-Based Playfair cipher. While in the second phase the encrypted data is steganographically hidden into some reference DNA sequence using an insertion technique.The proposed algorithm can successfully work on any binary data since it is actually transformed into a sequence of DNA nucleotides using some binary conversion rule. Subsequently, these nucleotides are represented as an amino acids structure in order to pass through the specially designed Playfair Cipher and encrypt it into another DNA sequence. Then, this encrypted DNA data is randomly inserted into some reference DNA sequence to produce a faked DNA sequence with the encrypted data hidden. In order to recover the embedded secret data, the receiver can carry out the inverse process with the help of the both the secret key and the reference DNA sequence.

Properties of DNA Complexes with New Cationic Surfactants

In this paper properties of deoxyribonucl eic acid (DNA) complexes with originally proposed cationic surfactants are described. Properties of prepared complexes were studied with the help of UV-vis-NIR and FT-IR spectroscopies, TGA and DSC analysis and X-ray diffractometry. These complexes are intended for future applications in organic electronics.

Influence of orientation on the piezoelectric properties of deoxyribonucleic acid

Abstract The piezoelectric properties of films of deoxyribonucleic acid (DNA) with different draw ratios have been studied. The values of piezoelectricity of DNA films strongly depend upon the draw ratio, with the constant increasing with increasing draw ratio. A maximum -d' 14 piezoelectric constant of 3.3 × 10−8 cgsesu was observed for a DNA film drawn to 1.5 times its original length. However, for a film with a draw ratio of 2.5, the maximum of -d' 14 can reach 10.2 × 10−8 cgsesu. The increase of piezoelectricity of DNA film is probably related to the existence of large number of spherulites and good molecular orientation caused by drawing.

Methylase activities from Haemophilus influenzae that protect Haemophilus parainfluenzae transforming deoxyribonucleic acid from inactivation by Haemophilus influenzae endonuclease R.

Specific methylases that have the properties of deoxyribonucleic acid (DNA) modification enzymes have been isolated from Haemophilus influenzae strain Rd. Two activities ((Methylase IIa and methylase III) were found to protect transforming DNA of H. parainfluenzae from the action of H. influenzae restriction enzymes. To determine the specificty of the protection, a procedure based on biological activity was developed for the separation and purification of the restriction endonucleases from H. influenzae strain Rd. Two endonuclease R activities presumably corresponding to Hind II and Hind III (P. H. Roy and H. O. Smith, 1973; H. O. Smith and K. W. Wilcox, 1970) were characterized by differences in their chromatographic properties, ability to attack T7 DNA, and inactivation of the transforming activity of different markers of H. parainfluenzae DNA. One endonuclease R enzyme (Hind II) attacked T7 DNA and was found to inactivate the dalacin resistance marker (smaller than 0.01% activity remaining) with only a slight effect on the streptomycin resistance marker (83% activity remaining). Methylase IIa treatment protected 40% of the dalacin resistance marker of H. parainfluenzae DNA from inactivation by Hind II. The other restriction activity (Hind III) was inert towards T7 DNA and inactivated the streptomycin resistance marker of H. parainfluenzae DNA (smaller than 0.01% activity remaining) without any effect on the dalacin resistance marker. The methylation of H. parainfluenzae DNA accomplished by methylase III protected 60% of the transforming activity of the streptomycin resistance marker of H. parainfluenzae DNA from the action of Hind III.

Isolation and Properties of Deoxyribonucleic Acid from Protoplasts of Cell Suspension Cultures of Ammi visnaga and Carrot (Daucus carota)

A procedure is described for the isolation of native DNA from protoplasts of ammi (Ammi visnaga) and carrot (Daucus carota) cells. Protoplasts were produced from 40 grams of fresh cells by enzyme hydrolysis and lysed with sodium dodecyl sulfate. The DNA was purified by treatment with pronase and ribonuclease. Final isolation was achieved by sucrose density gradient centrifugation.The melting temperature of ammi and carrot DNA in 0.15 m NaCl and 15 mm trisodium citrate buffer, pH 7.0, was 84.0 C and 84.5 C, respectively. The molecular weight for ammi DNA was 1.43 x 10(8), and for carrot DNA it was 1.56 x 10(8). Ammi DNA exhibited a single band at 1.690 grams per cubic centimeter in CsCl, whereas carrot DNA showed two bands, one at 1.693 grams per cubic centimeter and another at 1.706 grams per cubic centimeter. Ammi DNA consisted of a doublestranded form, since denaturation of the DNA caused a complete upward shift of 0.020 grams per cubic centimeter.

Some properties of deoxyribonucleic acid in competent Bacillus subtilis

Some properties of deoxyribonucleic acid in competent Bacillus subtilis

Protein synthesis during meiosis.

Studies on the behavior of chromosomes during the extended prophase of meiosis have been largely in the province of cytogenetics. Biochemical analyses have been few in number and these have centered on the properties of deoxyribonucleic acid (DNA). The significance of the meiotic history of DNA to chromosome pairing and crossing-over is patent, but the adequacy of such history in accounting for these two major phenomena is rendered improbable by the complexity of chromosome organization (luring meiotic prophase. The pioneering autoradiographic studies of Taylor' demonstrated the occurrence of protein synthesis during meiotic prophase, and his conclusions were subsequently confirmed in a general way by biochemical analysis.2 Other studies of meiotic proteins have been more specifically concerned with histones.3. 4 Taken as a whole, the attempts to define a relationship between proteins and the behavior of meiotic chromosomes have fallen short of their goal. Past studies only reveal that unidentified proteins are synthesized during meiotic prophase and that these proteins are located in both nucleus and cytoplasm. This report furnishes limited evidence for the selective synthesis of certain nuclear proteins during meiotic prophase and for their possible relationship to synapsis and crossing-over. The evidence is limited in the sense that no attempt has been made to survey all of the proteins synthesized during meiotic prophase nor to purify those proteins which appear to have a distinctive functional role. The purpose of these experiments has been to establish some temporal correlations between the synthesis of particular nuclear proteins and the behavior of chromosomes during meiotic prophase. Methods.-Meiotic cells obtained from two horticultural varieties of lily, Cinnabar and Bright Star, were cultured in vitro as described in an earlier publication.5 Protein synthesis was followed by the addition of uniformly labeled C14-leucine or H3-leucine (labeled in 4 and 5 positions) to the culture medium at concentrations of 0.25 ,c/ml or 2.5 yc/ml, respectively. HI-thymidine (methyl label) was used at a concentration of 10 ,uc/ml in studies of deoxyribonucleic acid (DNA) synthesis. The procedures used for harvesting the cells were the same as those previously described.6 Nuclei were isolated in glycerin-sucrose media.7 The nuclear fraction was homogenized in a glass tissue grinder with 25-50 vol of 0.1 M/ K-Na phosphate buffer (pH 8.0). The pestle was held in the chuck of a 1/4-in. electric drill controlled by a voltage regulator. The homogenate was allowed to stand in an ice bath for 20 min and then centrifuged for 10 min at 30,000 X g. The precipitate was re-extracted once and the combined supernatant fluids were dialyzed against 0.005 MA phosphate buffer (pH 8.8) for 2 hr with two changes of external medium. This extract will be referred to as the extract. The residue remaining after alkaline extraction was resuspended in 0.1 phosphate buffer (pH 6.0). The suspension was centrifuged at 30,000 X g for 10 min after standing in an ice bath for 20 min. The resulting supernatant fluid will be referred to as the pH 6.0 fraction. The residue was resuspended in NaCl containing 0.01 phosphate buffer (pH 7.0). The suspension was shaken overnight at 2?C and then centrifuged for 10 min at 10,000 X g. The supernatant fluid is designated as the 1.0 M fraction. The residue remaining will be referred to as such.

Effect of 6-azathymine on the isolation and properties of deoxyribonucleic acid from Streptococcus faecalis.

Effect of 6-azathymine on the isolation and properties of deoxyribonucleic acid from Streptococcus faecalis.

Macromolecular structure and properties of deoxyribonucleic acid

Macromolecular structure and properties of deoxyribonucleic acid

Alterations in Deoxyribonucleic Acid from Regenerating Rat Liver after X-radiation in vivo

WHILE it is thought that X-radiation in vivo does not produce any changes in the properties of deoxyribonucleic acid (DNA) which are associated with H bonding1, alterations in its structure are suggested from differences in fractionation pattern on ECTEOLA2,3 and from the diminished capacity of nuclei isolated after irradiation in vivo to act as templates for DNA synthesis4. The validity of the chromatographical evidence has been questioned for normal animals by Kondo and Osawa5 and after irradiation6,7, due to our ignorance of the means by which fractionation on ECTEOLA is attained and because of the possibility that the differences found between DNA from control and irradiated animals could be due to the action of DNases which are known to be activated in thymus after X-radiation. In view of these uncertainties, it was decided to extend our earlier observations on thymus DNA to regenerating rat liver. This tissue is advantageous since it is possible to irradiate at a known period in the mitotic cycle, and because in normal rat liver activation of DNases post-irradiation is much less marked than in thymus8. DNA was isolated by Kirby's method9, which would reduce to a minimum DNase action during the isolation.

Isolation and properties of deoxyribonucleic acid from mammalian sperm.

Isolation and properties of deoxyribonucleic acid from mammalian sperm.