DNA sequence homology between the terminal inverted repeats of Shope fibroma virus and an endogenous cellular plasmid species

DNA hybridization experiments indicate that the genome of a tumorigenic poxvirus. Shope fibroma virus (SFV), possesses sequence homology with DNA isolated from uninfected rabbit cells. Southern blotting experiments, either with high-complexity rabbit DNA as probe and SFV restriction fragments as targets or with high-specific activity, 32P-labeled, cloned SFV sequences as probes and rabbit DNA as target, indicate that the homologous sequences map at two locations within the viral genome, one in each copy of the terminal inverted repeat sequences. Unexpectedly, Southern blots revealed that the homologous host sequences reside in a rabbit extrachromosomal DNA element. This autonomous low-molecular-weight DNA species could be specifically amplified by cycloheximide treatment and was shown by isopycnic centrifugation in cesium chloride-ethidium bromide to consist predominantly of covalently closed circular DNA molecules. DNA sequencing of pSIC-9, a cloned 1.9-kilobase fragment of the rabbit plasmid species, indicated extensive homology at the nucleotide level over a 1.5-kilobase stretch of the viral terminal inverted repeat. Analysis of open reading frames in both the plasmid and SFV DNA revealed that (i) the N-terminal 157-amino acid sequence of a potential 514-amino acid SFV polypeptide is identical to the N-terminal 157 amino acids of one pSIC-9 open reading frame, and (ii) a second long pSIC-9 open reading frame of 361 amino acids, although significantly diverged from the comparable nucleotide sequence in the virus, possessed considerable homology to a family of cellular protease inhibitors, including alpha 1-antichymotrypsin, alpha 1-antitrypsin, and antithrombin III. The potential role of such cellular plasmid-like DNA species as a mediator in the exchange of genetic information between the host cell and a cytoplasmically replicating poxvirus is discussed.

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Sequence and structure of mtr, an amino acid transport gene of Neurospora crassa

Genome ◽

10.1139/g91-098 ◽

1991 ◽

Vol 34 (4) ◽

pp. 644-651 ◽

Cited By ~ 16

Author(s):

Kenneth Koo ◽

W. Dorsey Stuart

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Neurospora Crassa ◽

Rna Binding ◽

Signal Sequence ◽

Average Length ◽

Open Reading Frame ◽

Mrna Transcript ◽

S1 Nuclease ◽

Reading Frame

The gene product of the mtr locus of Neurospora crassa is required for the transport of neutral aliphatic and aromatic amino acids via the N system. We have previously cloned three cosmids containing Neurospora DNA that complement the mtr-6(r) mutant allele. The cloned DNAs were tightly linked to restriction fragment length polymorphisms that flank the mtr locus. A 2.9-kbp fragment from one cosmid was subcloned and found to complement the mtr-6(r) allele. Here we report the sequence of the fragment that hybridized to a poly(A)+ mRNA transcript of about 2300 nucleotides. We have identified an 845-bp open reading frame (ORF) having a 59-bp intron as the potential mtr ORF. S1 nuclease analysis of the transcript confirmed the transcript size and the presence of the intron. A second open reading frame was found upstream in the same reading frame as the mtr ORF and appears to be present in the mRNA transcript. The mtr ORF is predicted to encode a 261 amino acid polypeptide with a molecular mass of 28 613 Da. The proposed polypeptide exhibits six potential α-helical transmembrane domains with an average length of 23 amino acids, does not have a signal sequence, and contains amino acid sequence homologous to an RNA binding motif.Key words: sequence, membranes, ribonucleoprotein.

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Sequence and expression of the dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.6.5.1711-1721.1986 ◽

1986 ◽

Vol 6 (5) ◽

pp. 1711-1721

Author(s):

E M McIntosh ◽

R H Haynes

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acids ◽

Amino Acid ◽

Amino Acid Sequences ◽

Open Reading Frame ◽

Northern Analysis ◽

Hindiii Site ◽

Reading Frame ◽

Hindiii Restriction Site ◽

Cycle Dependent

The dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae has been isolated by screening a Sau3A clone bank for complementation of the dUMP auxotrophy exhibited by dcd1 dmp1 haploids. Plasmid pDC3, containing a 7-kilobase (kb) Sau3A insert, restores dCMP deaminase activity to dcd1 mutants and leads to an average 17.5-fold overproduction of the enzyme in wild-type cells. The complementing activity of the plasmid was localized to a 4.2-kb PvuII restriction fragment within the Sau3A insert. Subcloning experiments demonstrated that a single HindIII restriction site within this fragment lies within the DCD1 gene. Subsequent DNA sequence analysis revealed a 936-nucleotide open reading frame encompassing this HindIII site. Disruption of the open reading frame by integrative transformation led to a loss of enzyme activity and confirmed that this region constitutes the dCMP deaminase gene. Northern analysis indicated that the DCD1 mRNA is a 1.15-kb poly(A)+ transcript. The 5' end of the transcript was mapped by primer extension and appears to exhibit heterogeneous termini. Comparison of the amino acid sequence of the T2 bacteriophage dCMP deaminase with that deduced for the yeast enzyme revealed a limited degree of homology which extends over the entire length of the phage polypeptide (188 amino acids) but is confined to the carboxy-terminal half of the yeast protein (312 amino acids). A potential dTTP-binding site in the yeast and phage enzymes was identified by comparison of homologous regions with the amino acid sequences of a variety of other dTTP-binding enzymes. Despite the role of dCMP deaminase in dTTP biosynthesis, Northern analysis revealed that the DCD1 gene is not subject to the same cell cycle-dependent pattern of transcription recently found for the yeast thymidylate synthetase gene (TMP1).

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S elements: a family of Tc1-like transposons in the genome of Drosophila melanogaster.

Genetics ◽

10.1093/genetics/141.4.1425 ◽

1995 ◽

Vol 141 (4) ◽

pp. 1425-1438 ◽

Cited By ~ 1

Author(s):

P J Merriman ◽

C D Grimes ◽

J Ambroziak ◽

D A Hackett ◽

P Skinner ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Amino Acid ◽

Transposable Elements ◽

Sibling Species ◽

Inverted Repeat ◽

Open Reading Frame ◽

Drosophila Species ◽

Insertion Mutation ◽

Reading Frame ◽

Diploid Genome

Abstract The S elements form a diverse family of long-inverted-repeat transposons within the genome of Drosophila melanogaster. These elements vary in size and sequence, the longest consisting of 1736 bp with 234-bp inverted terminal repeats. The longest open reading frame in an intact S element could encode a 345-amino acid polypeptide. This polypeptide is homologous to the transposases of the mariner-Tc1 superfamily of transposable elements. S elements are ubiquitous in D. melanogaster populations and also appear to be present in the genomes of two sibling species; however, they seem to be absent from 17 other Drosophila species that were examined. Within D. melanogaster strains, there are, on average, 37.4 cytologically detectable S elements per diploid genome. These elements are scattered throughout the chromosomes, but several sites in both the euchromatin and beta heterochromatin are consistently occupied. The discovery of an S-element-insertion mutation and a reversion of this mutation indicates that S elements are at least occasionally mobile in the D. melanogaster genome. These elements seem to insert at an AT dinucleotide within a short palindrome and apparently duplicate that dinucleotide upon insertion.

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Nucleotide and Amino Acid Sequences of the Metallo-β-Lactamase, ImiS, from Aeromonas veronii bv. sobria

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.2.436 ◽

1998 ◽

Vol 42 (2) ◽

pp. 436-439 ◽

Cited By ~ 22

Author(s):

T. R. Walsh ◽

W. A. Neville ◽

M. H. Haran ◽

D. Tolson ◽

D. J. Payne ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Active Site ◽

Amino Acid Sequences ◽

Open Reading Frame ◽

Reading Frame ◽

Aeromonas Veronii ◽

Putative Active Site ◽

Lactamase Gene ◽

Active Site Sequence

ABSTRACT The Aeromonas veronii bv. sobria metallo-β-lactamase gene, imiS, was cloned. The imiS open reading frame extends for 762 bp and encodes a protein of 254 amino acids with a secreted modified protein of 227 amino acids and a predicted pI of 8.1. To confirm the predicted sequence, purified ImiS was digested and the resulting peptides were identified, yielding an identical sequence for ImiS, with 98% identity to CphA. Both possessed the putative active-site sequence Asn-Tyr-His-Thr-Asp at positions 88 to 92, which is unique to the Aeromonas metallo-β-lactamases.

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Sequence of the Structural Gene for Xanthine Dehydrogenase (rosy Locus) in Drosophila melanogaster

Genetics ◽

10.1093/genetics/116.1.67 ◽

1987 ◽

Vol 116 (1) ◽

pp. 67-73

Author(s):

Tim P Keith ◽

Margaret A Riley ◽

Martin Kreitman ◽

R C Lewontin ◽

Daniel Curtis ◽

...

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Drosophila Melanogaster ◽

Amino Acid ◽

Nucleotide Sequence ◽

Structural Gene ◽

Xanthine Dehydrogenase ◽

Open Reading Frame ◽

Reading Frame ◽

Eco Ri

ABSTRACT We determined the nucleotide sequence of a 4.6-kb Eco RI fragment containing 70% of the rosy locus. In combination with information on the 5′ sequence, the gene has been sequenced in entirety. rosy cDNAs have been isolated and intron/exon boundaries have been determined. We find an open reading frame which spans four exons and would encode a protein of 1335 amino acids. The molecular weight of the encoded protein (xanthine dehydrogenase), based on the amino acid translation, is 146,898 daltons which agrees well with earlier biophysical estimates. Characteristics of the protein are discussed.

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Sequence and expression of the dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae.

Molecular and Cellular Biology ◽

10.1128/mcb.6.5.1711 ◽

1986 ◽

Vol 6 (5) ◽

pp. 1711-1721 ◽

Cited By ~ 38

Author(s):

E M McIntosh ◽

R H Haynes

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acids ◽

Amino Acid ◽

Amino Acid Sequences ◽

Open Reading Frame ◽

Northern Analysis ◽

Hindiii Site ◽

Reading Frame ◽

Hindiii Restriction Site ◽

Cycle Dependent

The dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae has been isolated by screening a Sau3A clone bank for complementation of the dUMP auxotrophy exhibited by dcd1 dmp1 haploids. Plasmid pDC3, containing a 7-kilobase (kb) Sau3A insert, restores dCMP deaminase activity to dcd1 mutants and leads to an average 17.5-fold overproduction of the enzyme in wild-type cells. The complementing activity of the plasmid was localized to a 4.2-kb PvuII restriction fragment within the Sau3A insert. Subcloning experiments demonstrated that a single HindIII restriction site within this fragment lies within the DCD1 gene. Subsequent DNA sequence analysis revealed a 936-nucleotide open reading frame encompassing this HindIII site. Disruption of the open reading frame by integrative transformation led to a loss of enzyme activity and confirmed that this region constitutes the dCMP deaminase gene. Northern analysis indicated that the DCD1 mRNA is a 1.15-kb poly(A)+ transcript. The 5' end of the transcript was mapped by primer extension and appears to exhibit heterogeneous termini. Comparison of the amino acid sequence of the T2 bacteriophage dCMP deaminase with that deduced for the yeast enzyme revealed a limited degree of homology which extends over the entire length of the phage polypeptide (188 amino acids) but is confined to the carboxy-terminal half of the yeast protein (312 amino acids). A potential dTTP-binding site in the yeast and phage enzymes was identified by comparison of homologous regions with the amino acid sequences of a variety of other dTTP-binding enzymes. Despite the role of dCMP deaminase in dTTP biosynthesis, Northern analysis revealed that the DCD1 gene is not subject to the same cell cycle-dependent pattern of transcription recently found for the yeast thymidylate synthetase gene (TMP1).

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Structural and functional analyses of Saccharomyces cerevisiae wild-type and mutant RNA1 genes.

Molecular and Cellular Biology ◽

10.1128/mcb.9.7.2989 ◽

1989 ◽

Vol 9 (7) ◽

pp. 2989-2999 ◽

Cited By ~ 36

Author(s):

H M Traglia ◽

N S Atkinson ◽

A K Hopper

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Open Reading Frame ◽

Single Amino Acid ◽

Temperature Sensitive ◽

Wild Type ◽

Reading Frame ◽

Genomic Deletions ◽

Single Amino Acid Change ◽

Carboxy Terminal

The yeast gene RNA1 has been defined by the thermosensitive rna1-1 lesion. This lesion interferes with the processing and production of all major classes of RNA. Each class of RNA is affected at a distinct and presumably unrelated step. Furthermore, RNA does not appear to exit the nucleus. To investigate how the RNA1 gene product can pleiotropically affect disparate processes, we undertook a structural analysis of wild-type and mutant RNA1 genes. The wild-type gene was found to contain a 407-amino-acid open reading frame that encodes a hydrophilic protein. No clue regarding the function of the RNA1 protein was obtained by searching banks for similarity to other known gene products. Surprisingly, the rna1-1 lesion was found to code for two amino acid differences from wild type. We found that neither single-amino-acid change alone resulted in temperature sensitivity. The carboxy-terminal region of the RNA1 open reading frame contains a highly acidic domain extending from amino acids 334 to 400. We generated genomic deletions that removed C-terminal regions of this protein. Deletion of amino acids 397 to 407 did not appear to affect cell growth. Removal of amino acids 359 to 397, a region containing 24 acidic residues, caused temperature-sensitive growth. This allele, rna1-delta 359-397, defines a second conditional lesion of the RNA1 locus. We found that strains possessing the rna1-delta 359-397 allele did not show thermosensitive defects in pre-rRNA or pre-tRNA processing. Removal of amino acids 330 to 407 resulted in loss of viability.

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Structure-Based Engineering of an Artificially Generated NADP+-Dependent d-Amino Acid Dehydrogenase

Applied and Environmental Microbiology ◽

10.1128/aem.00491-17 ◽

2017 ◽

Vol 83 (11) ◽

Cited By ~ 6

Author(s):

Junji Hayashi ◽

Tomonari Seto ◽

Hironaga Akita ◽

Masahiro Watanabe ◽

Tamotsu Hoshino ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Substrate Specificity ◽

Specific Activity ◽

High Specific Activity ◽

Site Directed Mutagenesis ◽

Directed Mutagenesis ◽

High Catalytic Activity ◽

Acid Dehydrogenase ◽

Amino Acid Dehydrogenase

ABSTRACT A stable NADP+-dependent d-amino acid dehydrogenase (DAADH) was recently created from Ureibacillus thermosphaericus meso-diaminopimelate dehydrogenase through site-directed mutagenesis. To produce a novel DAADH mutant with different substrate specificity, the crystal structure of apo-DAADH was determined at a resolution of 1.78 Å, and the amino acid residues responsible for the substrate specificity were evaluated using additional site-directed mutagenesis. By introducing a single D94A mutation, the enzyme's substrate specificity was dramatically altered; the mutant utilized d-phenylalanine as the most preferable substrate for oxidative deamination and had a specific activity of 5.33 μmol/min/mg at 50°C, which was 54-fold higher than that of the parent DAADH. In addition, the specific activities of the mutant toward d-leucine, d-norleucine, d-methionine, d-isoleucine, and d-tryptophan were much higher (6 to 25 times) than those of the parent enzyme. For reductive amination, the D94A mutant exhibited extremely high specific activity with phenylpyruvate (16.1 μmol/min/mg at 50°C). The structures of the D94A-Y224F double mutant in complex with NADP+ and in complex with both NADPH and 2-keto-6-aminocapronic acid (lysine oxo-analogue) were then determined at resolutions of 1.59 Å and 1.74 Å, respectively. The phenylpyruvate-binding model suggests that the D94A mutation prevents the substrate phenyl group from sterically clashing with the side chain of Asp94. A structural comparison suggests that both the enlarged substrate-binding pocket and enhanced hydrophobicity of the pocket are mainly responsible for the high reactivity of the D94A mutant toward the hydrophobic d-amino acids with bulky side chains. IMPORTANCE In recent years, the potential uses for d-amino acids as source materials for the industrial production of medicines, seasonings, and agrochemicals have been growing. To date, several methods have been used for the production of d-amino acids, but all include tedious steps. The use of NAD(P)+-dependent d-amino acid dehydrogenase (DAADH) makes single-step production of d-amino acids from oxo-acid analogs and ammonia possible. We recently succeeded in creating a stable DAADH and demonstrated that it is applicable for one-step synthesis of d-amino acids, such as d-leucine and d-isoleucine. As the next step, the creation of an enzyme exhibiting different substrate specificity and higher catalytic efficiency is a key to the further development of d-amino acid production. In this study, we succeeded in creating a novel mutant exhibiting extremely high catalytic activity for phenylpyruvate amination. Structural insight into the mutant will be useful for further improvement of DAADHs.

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CHARACTERIZATION OF THE WHEAT cDNA ENCODING THE β SUBUNIT OF THE MITOCHONDRIAL ATP SYNTHASE

Israel Journal of Plant Sciences ◽

10.1080/07929978.1996.10676637 ◽

1996 ◽

Vol 44 (2-3) ◽

pp. 77-88 ◽

Cited By ~ 1

Author(s):

Suzy Abulafia ◽

Dan Graur ◽

Katrien Devos ◽

Adina Breiman

Keyword(s):

Amino Acids ◽

Phylogenetic Analysis ◽

Amino Acid ◽

Open Reading Frame ◽

Β Subunit ◽

Reading Frame ◽

Mitochondrial Atp Synthase ◽

Group 1 Chromosomes ◽

Group 1

A wheat cDNA encoding an open reading frame of 553 amino acids with a deduced amino acid sequence corresponding to the mitochondrial β subunit of the synthase was isolated. The expression of the β ATPase was investigated in leaves of 7-day-old wheat plants, and a decrease in the abundance of transcripts along the leaf was observed. The cDNA of the β ATPase was mapped on the group 1 chromosomes of wheat. Phylogenetic analysis of the mitochondrial β subunit of the ATPase complex is described.

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