Complete nucleotide sequence of mini-Rts1 and its copy mutant.

The nucleotide sequence of the whole mini-Rts1 genome consisting of 1,855 base pairs was determined. In addition to the cluster of five 24-base-pair direct repeats previously detected (Y. Kamio and Y. Terawaki, J. Bacteriol. 155:1185-1191, 1983), another cluster of three 21-base-pair direct repeats was found. All eight repeats were located in one direction and contained a consensus sequence TTCCCCPyPyPuPuCACACACC. Between the two clusters, a large open reading frame that could encode a 32,980-dalton polypeptide consisting of 288 amino acids was assigned. The molecular size predicted from the amino acid composition was close to the value of a unique mini-Rts1 product, the RepA protein, newly determined in minicells. A copy mutant of mini-Rts1 obtained in vitro by hydroxylamine treatment contained two-base-pair substitutions, one of which was located in the RepA protein coding region, and the other was close to the region where the oriC homologous sequences exist.     

Azotobacter vinelandii mutS: nucleotide sequence and mutant analysis.

An Azotobacter vinelandii homolog to the Salmonella typhimurium mutS gene was discovered upstream of the fdxA gene. The product of this gene is much more similar to S. typhimurium MutS than either is to the HexA protein of Streptococcus pneumoniae. An A. vinelandii delta mutS mutant strain was shown to have a spontaneous mutation frequency 65-fold greater than that of the wild type.     

Identification and nucleotide sequence of the activator gene of the externally induced phosphoglycerate transport system of Salmonella typhimurium

A recent study from this laboratory (G-q. Yu, D. Goldrick, H.R. Kaback and J-s. Hong, in preparation) indicates that the externally induced phosphoglycerate transport system (pgt) of Salmonella typhimurium is positively regulated by the activator gene, pgtA, and that the pgtA is localized in the SalI-PstI restriction fragment 3.0 kb from the permease gene, pgtP. In this paper, we describe the identification of the activator gene and its gene product and the determination of the complete nucleotide (nt) sequence of the activator gene as well as of a downstream gene not required for pgtP expression. The amino acid sequence of the activator based on the nt sequence shows an N-terminal signal-like sequence which is apparently not cleaved and three potential transmembrane sequences in the C-terminal half of the protein based on the hydropathy analysis.     

The nucleotide sequence of the yeast MEL1 gene.

The complete nucleotide sequence of the MEL1 gene of the yeast, Saccharomyces cerevisiae, encoding alpha-galactosidase was determined. The nucleotide sequence contains an open reading frame of 1413 bp encoding a protein of 471 amino acids. Comparison with the known N-terminal amino acid sequence of the mature secreted protein indicated that alpha-galactosidase is synthesized as a precursor with an N-terminal signal sequence of 18 amino acids. The general features of this signal peptide resemble those of other yeast signal peptides. Molecular weight of the mature alpha-galactosidase polypeptide deduced from the nucleotide sequence is 50.049 kd. The 5' regulatory region has sequences in common with other yeast genes regulated by the GAL4-protein.     

Cloning, expression, and nucleotide sequence of a mutant glgC gene from Escherichia coli B.

A mutant glgC gene contained in a 10.9-kb PstI fragment was cloned from the Escherichia coli B strain SG5 via colony hybridization by using a wild-type glgC probe. The altered allosteric properties of the expressed ADPglucose synthetase were found to result from the conversion of proline to serine at amino acid residue 295.     

The nucleotide sequence of the mitochondrial DNA genome of an abundant petite mutant of Saccharomyces cerevisiae carrying the ori1 replication origin

We have determined the 903 bp nucleotide sequence of the mitochondrial DNA genome of a Saccharomyces cerevisiae petite mutant BB5. This petite, containing the 265 nucleotide ori1 region, is representative of a class of petites arising at exceptionally high frequency within the population of spontaneous petites derived from a particular mit- strain Mb12. The DNA sequences of both the ori1 region and the flanking intergenic regions have been compared to those of the corresponding regions of mtDNA in a previously reported petite strain, a1/1R/1 of Bernardi's laboratory, that has a similar (880 bp) repeat unit. The BB5 petite genome carries a canonical ori1 sequence that is identical in both petite mtDNAs, but the flanking intergenic sequences show significant differences between the two petite strains. The divergence is considered to arise from differences in the sequences flanking ori1 in the respective parent strains.     

Genomic sequence of C1, the first streptococcal phage

C(1), a lytic bacteriophage infecting group C streptococci, is one of the earliest-isolated phages, and the method of bacterial classification known as phage typing was defined by using this bacteriophage. We present for the first time a detailed analysis of this phage by use of electron microscopy, protein profiling, and complete nucleotide sequencing. This virus belongs to the Podoviridae family of phages, all of which are characterized by short, noncontractile tails. The C(1) genome consists of a linear double-stranded DNA molecule of 16,687 nucleotides with 143-bp inverted terminal repeats. We have assigned functions to 9 of 20 putative open reading frames based on experimental substantiation or bioinformatic analysis. Their products include DNA polymerase, holin, lysin, major capsid, head-tail connector, neck appendage, and major tail proteins. Additionally, we found one intron belonging to the HNH endonuclease family interrupting the apparent lysin gene, suggesting a potential splicing event yielding a functional lytic enzyme. Examination of the C(1) DNA polymerase suggests that this phage utilizes a protein-primed mechanism of replication, which is prominent in the phi29-like members of Podoviridae. Consistent with this evidence, we experimentally determined that terminal proteins are covalently attached to both 5' termini, despite the fact that no homology to known terminal proteins could be elucidated in any of our open reading frames. Likewise, comparative genomics revealed no close evolutionary matches, suggesting that the C(1) bacteriophage is a unique member of the Podoviridae.     

Identification of the Klebsiella pneumoniae glnB gene: nucleotide sequence of wild-type and mutant alleles

Summary The glnB gene of Klebsiella pneumoniae, which encodes the nitrogen regulation protein P_II has been cloned and sequenced. The gene encodes a 12429 dalton polypeptide and is highly homologous to the Escherichia coli glnB gene. The sequences of a glnB mutation which causes glutamine auxotrophy and of a Tn5 induced Gln⁺ suppressor of this mutation were also determined. The glutamine auxotrophy was deduced to be the result of a modification of the uridylylation site of P_II and the suppression was shown to be caused by Tn5 insertion in glnB. The 3 end of an open reading frame of unknown function was identified upstream of glnB and may be part of an operon containing glnB. Potential homologues of glnB encoding polypeptides extremely similar in sequence to P_II were identified upstream of published sequences of the glutamine synthetase structural gene (glnA) in Rhizobium leguminosarum, Bradyrhizobium japonicum and Azospirillum brasilense.     

The nucleotide sequence of the rep gene of cyanobacterial plasmid pSM1

The nucleotide sequence was established for the rep gene of plasmid pSM1 isolated from cyanobacterium Plectonema boryanum CALU 465. Both nucleotide sequence and the encoded amino acid sequences showed 98% homology to the corresponding sequences of small plasmids pPF1, pGL3, pPBS1, pBLX, and pPB1. An active center was identified in the replicative protein sequences.