Complete nucleotide sequence and genome organization of bovine parvovirus.

We determined the complete nucleotide sequence of bovine parvovirus (BPV), an autonomous parvovirus. The sequence is 5,491 nucleotides long. The terminal regions contain nonidentical imperfect palindromic sequences of 150 and 121 nucleotides. In the plus strand, there are three large open reading frames (left ORF, mid ORF, and right ORF) with coding capacities of 729, 255, and 685 amino acids, respectively. As with all parvoviruses studied to date, the left ORF of BPV codes for the nonstructural protein NS-1 and the right ORF codes for the major parts of the three capsid proteins. The mid ORF probably encodes the major part of the nonstructural protein NP-1. There are promoterlike sequences at map units 4.5, 12.8, and 38.7 and polyadenylation signals at map units 61.6, 64.6, and 98.5. BPV has little DNA homology with the defective parvovirus AAV, with the human autonomous parvovirus B19, or with the other autonomous parvoviruses sequenced (canine parvovirus, feline panleukopenia virus, H-1, and minute virus of mice). Even though the overall DNA homology of BPV with other parvoviruses is low, several small regions of high homology are observed when the amino acid sequences encoded by the left and right ORFs are compared. From these comparisons, it can be shown that the evolutionary relationship among the parvoviruses is B19 in equilibrium with AAV in equilibrium with BPV in equilibrium with MVM. The highly conserved amino acid sequences observed among all parvoviruses may be useful in the identification and detection of parvoviruses and in the design of a general parvovirus vaccine.     

Structural organization of transposable element mdg4 from Drosophila melanogaster and a nucleotide sequence of its long terminal repeats

A mobile dispersed genetic element, mdg4 , approximately 7.5 kilobases (kb) long has been cloned from D. melanogaster genome. Chromosomal bands have only few sites of mdg4 , but it always hybridizes to the chromocenter. The location of mdg4 varies among D. melanogaster strains. Blot hybridization shows that, in contrast to other mdg elements, mdg4 sequences are rather heterogeneous. Only few copies are full-length. A strong amplification of mdg4 has occurred during the in vitro cultivation of cells involving only one mdg4 variant. Long terminal repeats (LTRs) and flanking sequences have been sequenced in two cloned copies of transposable element mdg4 . In both cloned copies of mdg4 , LTRs have an identical nucleotide sequence 479 bp long. The mdg4 is flanked by four-base-pair direct repeats, short mismatched palindromes being present at the ends of each LTR. The termini of the mdg4 body contain an oligopurine stretch and a region partially complementary to D. melanogaster tRNA-Lys. Thus, structural organization of mdg4 LTRs is similar to that of several other mdg elements and retroviral proviruses.     

Complete nucleotide sequence and genome organization of tobacco mosaic virus isolated from Viciafaba

Based on reported TMV-U1 sequence, primers were designed and fragments covering the entire genome of TMV broad bean strain (TMV-B) were obtained with RT-PCR. These fragments were cloned and sequenced and the 5' and 3' end sequences of genome were confirmed with RACE. The complete sequence of TMV-B comprises 6 395 nucleotides (nt) and four open reading frames, which correspond to 126 ku (1 116 amino acids), 183 ku (1 616 amino acids), 30 ku (268 amino acids) and 17.5 ku proteins (159 amino acids). The complete nucleotide sequence of TMV-B is 99.4% identical to that of TMV-U1. The two virus isolates share the same sequence of 5', 3' non-coding region and 17.5 K ORF, and 6, 1 and 3 amino acid changes are found in 126 K protein, 54 K protein and 30 K protein, respectively. The possible mechanism on the infection of TMV-B in Vicia faba is discussed.     

Complete nucleotide sequence and genetic organization of the bacteriocinogenic plasmid, pIP404, from Clostridium perfringens

The complete nucleotide sequence of the bacteriocinogenic plasmid, pIP404, from Clostridium perfringens has been determined. The plasmid genome comprises 10,207 bp and has a dA + dT content of 75%. Functions have been tentatively assigned to 6 of the 10 open reading frames and an origin-like region of repeated sequence identified. The codon usage of this extremely dA + dT rich plasmid is highly unusual and displays a pronounced preference for codons with the lowest dG + dC content. Only one of the genes from pIP404 was expressed at a significant level in Escherichia coli, suggesting that the atypical codon usage could represent a major obstacle to heterologous gene expression.     

Complete nucleotide sequence of thePorphyra purpurea chloroplast genome

The complete nucleotide sequence of the chloroplast genome of the red algaPorphyra purpurea has been determined (accession number=U38804). The circular genome is 191,028 bp in length and encodes approximately 250 genes.     

Complete nucleotide sequence and genome organization of tobacco mosaic virus isolated fromVicia faba

Based on reported TMV-U1 sequence, primers were designed and fragments covering the entire genome of TMV broad bean strain (TMV-B) were obtained with RT-PCR. These fragments were cloned and sequenced and the 5’ and 3’ end sequences of genome were confirmed with RACE. The complete sequence of TMV-B comprises 6 395 nucleotides (nt) and four open reading frames, which correspond to 126 ku (1 116 amino acids), 183 ku (1 616 amino acids), 30 ku (268 amino acids) and 17.5 ku proteins (159 amino acids). The complete nucleotide sequence of TMV-B is 99.4% identical to that of TMV-U1. The two virus isolates share the same sequence of 5’, 3’ non-coding region and 17.5 K ORF, and 6, 1 and 3 amino acid changes are found in 126 K protein, 54 K protein and 30 K protein, respectively. The possible mechanism on the infection of TMV-B inVicia faba is discussed.     

Complete nucleotide sequence of the mitochondrial genome of a salamander, Mertensiella luschani

The complete nucleotide sequence (16,650 bp) of the mitochondrial genome of the salamander Mertensiella luschani (Caudata, Amphibia) was determined. This molecule conforms to the consensus vertebrate mitochondrial gene order. However, it is characterized by a long non-coding intervening sequence with two 124-bp repeats between the tRNA(Thr) and tRNA(Pro) genes. The new sequence data were used to reconstruct a phylogeny of jawed vertebrates. Phylogenetic analyses of all mitochondrial protein-coding genes at the amino acid level recovered a robust vertebrate tree in which lungfishes are the closest living relatives of tetrapods, salamanders and frogs are grouped together to the exclusion of caecilians (the Batrachia hypothesis) in a monophyletic amphibian clade, turtles show diapsid affinities and are placed as sister group of crocodiles+birds, and the marsupials are grouped together with monotremes and basal to placental mammals. The deduced phylogeny was used to characterize the molecular evolution of vertebrate mitochondrial proteins. Amino acid frequencies were analyzed across the main lineages of jawed vertebrates, and leucine and cysteine were found to be the most and least abundant amino acids in mitochondrial proteins, respectively. Patterns of amino acid replacements were conserved among vertebrates. Overall, cartilaginous fishes showed the least variation in amino acid frequencies and replacements. Constancy of rates of evolution among the main lineages of jawed vertebrates was rejected.     

The nucleotide sequence and protein-coding capability of the transposable element IS5

The nucleotide sequence of IS5, a bacterial insertion sequence, has been determined. It is 1195 bp long and contains an inverted terminal repetition of 16 bp with one mismatch. One open reading frame, spanning nearly the entire length of the element, could encode a polypeptide of 338 amino acids. Upon insertion into a DNA segment, IS5 causes a duplication of 4 bp. Based on seven examples, this site of insertion appears to be nonrandom, and the consensus target site sequence is C . T/A . A . G/A (or C/T . T . A/T . G on the opposite strand). The nucleotide sequences of IS5 insertions into the B and cim genes of bacteriophage Mu have allowed tentative identification of the protein-coding frames of B and cim.     

Complete nucleotide sequence and organization of the mitochondrial genome of eri-silkworm,Samia cynthia ricini (Lepidoptera: Saturniidae)

Samia cynthia ricini is a commercial silk-producing insect that is now reared year-round in Korea, with the expectation of being utilized for diverse purposes. In this report, we present the complete mitochondrial genome (mitogenome) of S. c. ricini. The 15,384-bp long S. cynthia ricini mitogenome was amplified into 26 short fragments using three long overlapping fragments using primers designed from reported lepidopteran mitogenome sequences. The genome comprises 37 genes (13 protein-coding genes, two rRNA genes, and 22 tRNA genes), and one large non-coding region termed the A + T-rich region. The A/T content of the third codon position was 91.7%, which was 18.8% and 21.6% higher than those of first and second codon positions, respectively. The high A/T content in the genome is reflected in codon usage, accounting for 39.5% of A/T-composed codons (TTA, ATT, TTT, and ATA). Unlike a previous report on the start codon for the COI gene, the S. c. ricini COI gene commences with a typical ATT codon. A total of 221 bp of non-coding sequences are dispersed in 17 regions, ranging in size from 1 to 54 bp, which comprise 1.4% of the total genome. One of the non-coding sequence located between tRNA^Gln and ND2 (54 bp) has 77% sequence homology with the 5′-sequence of the neighboring ND2 gene, suggesting partial duplication of the sequence during evolution. The 361-bp long A + T-rich region contains an 18 bp-long poly-T stretch, ATAGA motif, ATTTA element, microsatellite-like A/T sequence, poly-A stretch and one tRNA-like sequence, as typically found in Lepidoptera including Bombycoidea.     

Gene distribution and nucleotide sequence organization in the mouse genome

Mouse DNA was fractionated by preparative centrifugation in density gradients of Cs2SO4 containing 3,6-bis(acetatomercurimethyl)dioxane (BAMD). The effects of temperature, BAMD/nucleotide molar ratio and solvent on the fractionation were explored. The fractions so obtained were investigated by analytical centrifugation in CsCl density gradient and by hybridization with a number of gene probes. These approaches led to the definition of satisfactory conditions for the rapid fractionation of mouse DNA; to the localization of a number of genes in mouse DNA fractions; and to a better understanding of the mosaic organization of the mouse genome and, more specifically, to a better estimate of both the intermolecular and intramolecular compositional heterogeneity of mouse DNA in the (75-150) X 10(3)-base size range.     

Gene distribution and nucleotide sequence organization in the human genome

Human DNA was fractionated by centrifugation in Cs2SO4 density gradients containing 3,6-bis(acetatomercurimethyl)dioxane (BAMD). Fractions were investigated in their analytical CsCl profiles and a number of specific sequences were localized in them. The results so obtained led to an improved understanding of the organization of nucleotide sequences in the human genome, as well as to the discovery that a class of DNA having a very high G + C content and not represented in the mouse genome, is particularly rich in genes and interspersed repetitive sequences.     

Complete nucleotide sequence and gene organization of plasmid NTP16.

We have determined the complete nucleotide sequence of the 8.3-kb multicopy plasmid NTP16 and produced a functional map of its gene organization. Sixty percent of the plasmid DNA comprises transposon-derived sequences; in the remaining 3320 bp, we have identified three protein coding regions. NTP16 has a ColE1-type replication system, a cis-acting stability locus and a mobilization system comprising an oriT site and one mobilization protein. The roles of the other two protein products of this plasmid are unknown, but they are possibly involved in the plasmid incompatibility system.     

Complete nucleotide sequences and gene organization of mitochondrial genome of Bufo gargarizans

The complete mitochondrial genome of Bufo gargarizans was sequenced using overlapping polymerase chain reaction (PCR) amplicons (GenBank Accession No. DQ275350). The genome is 17,277 base pairs in length, containing 13 protein-coding genes (ATP6, ATP8, COI-III, ND1-6, ND4L, Cyt b), 2 ribosomal RNAs (12S rRNA and 16S rRNA), 22 transfer RNAs and a putative control region. We analyzed the sequence using bioinformatics methods comparing the obtained mtDNA sequence with other toads and frogs. Based on the concatenated nucleotide sequences of protein-coding genes, we constructed a phylogenetic tree with maximum likelihood (ML) and maximum parsimony (MP) methods and discussed the phylogenetic relationships among 11 species of Anura.     

Complete nucleotide sequence of the Eastern equine encephalomyelitis virus genome

The complete nucleotide sequence of the genomic 42S RNA of Eastern equine encephalitis virus has been defined for the first time. The strategy of this viral genome occurred analogous to the ones of the other alfa viruses. The comparison of amino acid sequences of E1 and E2 proteins from the two strains of the virus has revealed a number of differences. Partially, they are localized in the hydrophilic regions of the protein molecules and evidently participate in organization of the specific antigenic structures. The amino acid sequences of all viral proteins have been comparatively analysed with the sequences of the analogous proteins of other known alfa viruses.     

Complete nucleotide sequence of the mycoplasma virus P1 genome

Mycoplasma virus P1 is one of only four viruses isolated from the genus Mycoplasma. The host for P1, Mycoplasma pulmonis, possesses complex, phase-variable restriction and modification enzymes and the Vsa family of phase-variable surface proteins. The ability of P1 virus to infect host cells is influenced by these phase-variable systems, rendering P1 a valuable tool for assessing host properties. The double-stranded P1 DNA genome was sequenced (11,660 bp) and 11 ORFs were identified. The predicted P1 DNA polymerase is similar to that of phages that are known to have terminal protein (TP) attached to the 5' end of their genome, consistent with previous studies indicating that P1 DNA has covalently attached TP. Most of the other predicted P1 proteins have little sequence similarity to known proteins, and P1 virus is unrelated to the other mycoplasma virus, MAV1, for which the genome sequence is known. One of the predicted P1 proteins, the ORF 8 gene product, contains a repetitive collagen-like motif characteristic of some bacteriophage tail fiber proteins and is a candidate for interacting with the Vsa proteins.