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A V Kaliman

Publications and source records attributed to A V Kaliman.

At least 19 recordsLinked to original sources
PubMed1996

Identification of the bacteriophage T5 dUTPase by protein sequence comparisons.

It is shown by protein sequence comparisons that a 148 amino acid open reading frame (ORF 148) located at 67% of the bacteriophage T5 genome encodes a protein with strong similarity to known dUTPases. This protein contains five characteristic amino acid sequence motifs that are common to the dUTPase gene family. A similarity in size and high degree of sequence identity strongly suggest that the protein encoded by the ORF 148 of bacteriophage T5 is dUTPase.

Amino Acid Sequence↗
PubMed1995

The nucleotide sequence of the bacteriophage T5 ltf gene.

The nucleotide sequence of the bacteriophage T5 Bg/II-BamHI fragment (4,835 bp in length) known to carry a gene encoding the LTF protein which forms the phage L-shaped tail fibers was determined. It was shown to contain an open reading frame for 1,396 amino acid residues that corresponds to a protein of 147.8 kDa. The coding region of ltf gene is preceded by a typical Shine-Dalgarno sequence. Downstream from the ltf gene there is a strong transcription terminator. Data bank analysis of the LTF protein sequence reveals 55.1% identity to the hypothetical protein ORF 401 of bacteriophage lambda in a segment of 118 amino acids overlap.

Amino Acid Sequence↗
PubMed1994

Large and small subunits of the Aujeszky's disease virus ribonucleotide reductase: nucleotide sequence and putative structure.

We determined the entire DNA sequence of two adjacent open reading frames of Aujeszky's disease virus encoding ribonucleotide reductase genes with the intergenic sequence of 9 bp. From the sequence analysis we deduce that ORFs encode large and small subunits, with sizes of 835 and 303 amino acids, respectively. Amino acid sequence comparison of ADV RR2 with that of equine herpesvirus type 1, bovine herpesvirus type 1, HSV-1 and varicella zoster virus revealed that 48% of amino acids represent clusters of residues conserved in all compared sequences. In the N-terminal part ADV RR1 shows low homology to the RR1 of other herpesviruses. Rest of the RR1 protein contains highly conserved amino acid sequences divided by blocks of low homology.

Amino Acid Sequence↗
PubMed1994

Sense antisense DNA strand?

Recent evidence indicates that alphaherpesviruses express latency associated transcripts (LATs) from the antisense strand of immediate-early (IE) genes of the viral genome. It has been suggested that LATs containing extended open reading frames (ORFs), might be translated into (a) protein product(s). We found that a salient feature of some herpesvirus DNAs is a high GC preference at the third codon positions. The consequence of this feature is that the probability of a stop-codon appearing at two of the six reading frames of the DNA strand is very low. Therefore, the presence of an extended ORF does not necessarily mean that it is relevant to real translation.

Base Sequence↗
PubMed1994

Structural features of the ribonucleotide reductase of Aujeszky's disease virus.

A gene construct of the Aujeszky's disease virus (ADV) genome was prepared and the DNA fragment encoding the ribonucleotide reductase was structurally characterized. We determined the entire DNA sequence of two adjacent open reading frames of the ribonucleotide reductase genes with the intergenic sequence of nine base pairs. From the sequence analysis we predict that Aujeszky's disease virus encodes a ribonucleotide reductase which comprises two polypeptides--large and small subunits, with sizes of 835 and 303 amino acids, respectively. Nucleotide and amino acid sequences of the large and small subunits of the Aujeszky's disease virus ribonucleotide reductase have been compared with that of other herpesviruses, and structural features of both proteins have been characterized.

Amino Acid Sequence↗
PubMed1989

Two early genes of bacteriophage T5 encode proteins containing an NTP-binding sequence motif and probably involved in DNA replication, recombination and repair.

It is demonstrated, by computer-assisted analysis, that T5 bacteriophage early genes D10 and D13 encode proteins containing the purine NTP-binding sequence motif. The D10 gene product is shown to be a member of a recently characterized superfamily of (putative) DNA and RNA helicases. The D13 gene product is related at a statistically significant level, to the gene 46 product of bacteriophage T4 which is a component of an exonuclease involved in phage DNA replication, recombination and repair. A lower but also significant degree of sequence similarity was detected between the gene D12 product of T5 and the gene 47 product of T4, the second component of the same nuclease. It is hypothesized that both D10 and D13 gene products of T5 might be NTPases, possibly DNA-dependent, mediating NTP-consuming steps during phage DNA replication, recombination and/or repair.

Amino Acid Sequence↗
PubMed1987

[The structure of 2 promoters and a transcription terminator from the region of early genes D10-D15 of bacteriophage T5].

The primary structures of two promoters (T5 P31A and T5 P31B) and transcription terminator from the region of bacteriophage T5 early genes D10-D15 were determined. Both promoters (62% of the phage T5 DNA physical map) are located as a tandem at 70 bp distance from each other and are typical for the promoter-consensus structure of DNA of bacteriophage T5 early promoters. The transcription terminator is located in the region of the BamHI site (67% of the phage T5 DNA physical map) and is arranged in good coincidence with the consensus structure of the already known rho-independent terminators of various organisms. The promotor T5 P31A and the terminator were tested for the level of galactokinase synthesis using galK gene-carrying plasmids and D-14C-galactose as a substrate for galactokinase.

Base Sequence↗
PubMed1987

[Various characteristics of the anti-restriction mechanism in bacteriophage T5].

Bacteriophage T5 is not confined by the restriction systems of the second type EcoRII and EcoRV. Bacteriophage T5 DNA is not modified by EcoRII and EcoRV methylases in vivo. The sites of recognition for restriction endonuclease EcoRV are mapped at 24.4; 57.6; 68.5; 70.2% of T5 DNA, while the sites at 5.1; 7.6% are recognized by EcoRII, the sites at 5.75; 6.0 and 6.5% are recognized by HpaI in FST. A high activity of restriction endonucleases EcoRI and EcoRV is demonstrated in crude extracts of E. coli B834 (RI) and E. coli B834 (RV) cells infected by bacteriophage T5. The simultaneous infection of E. coli B834 (RI) or E. coli B834 (RV) cells by the amber mutants of bacteriophage T5 and the suppressing phage lambda NM761 does not result in the protection of lambda DNA by the T5 anti-restriction mechanism. The presented data support the hypothesis that the anti-restriction mechanism of bacteriophage T5 is based on prevention of T5 DNA contacts with restriction enzymes by a specific phage protein.

DNA Restriction Enzymes↗
PubMed1987

[Primary structure of proline tRNA of bacteriophage T5].

The uniformly 32P-labeled bacteriophage T5 proline tRNA has been isolated from phage-infected E. coli cells by two-dimensional PAGE. Its nucleotide sequence has been determined by conventional techniques (using TLC on cellulose for oligonucleotide fractionation) as follows: (Formula: see text). The tRNA has the anticodon sequence UGG, which can presumably recognize the four proline-specific codons (CCN). It has 70% homology with phage T4 tRNA(Pro).

Base Sequence↗
PubMed1986

Cloning and DNA sequence of the 5'-exonuclease gene of bacteriophage T5.

The nucleotide sequence of the BalI-PstI fragment of T5 DNA, 1347 bp in length, coding for 5'-exonuclease (D15 gene), has been determined. A coding region of the gene contains 873 bp and is preceded by a typical Shine-Dalgarno sequence. The D15 gene belongs to a cluster, consisting of at least 3 genes, in which a termination codon of a preceding gene overlaps an initiation codon of the following one. The sequence contains an open reading frame for 291 amino acid residues. The molecular mass of the 5'-exonuclease calculated from the predicted amino acid sequence is 33 400 Da.

Amino Acid Sequence↗
PubMed1984

The nucleotide sequence of bacteriophage T5 glutamine transfer RNA.

Uniformly 32P-labeled phage-specific tRNAGln has been isolated from bacteriophage T5-infected Escherichia coli cells and its nucleotide sequence has been determined using thin-layer chromatography on cellulose to fractionate the oligonucleotides. The sequence is: pUGGGGAUUAGCUUAGCUUGGCCUAAAGCUUCGGCCUUUGAAG psi CGAGAUCAUUGGT psi CAAAUCCAAUAUCCCCUGCCAOH. The main feature of this tRNA is the absence of Watson-Crick pairing between the 5'-terminal base and the fifth base from its 3'-end. The structure of tRNA was confirmed by DNA sequencing of its gene.

Base Sequence↗