Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “inverted terminal repeat”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,747 records · Page 97Linked to original sources
PubMed1987

A genomic clone containing the promoter for the gene encoding the human lysosomal enzyme, alpha-galactosidase A.

We have isolated and characterized a human genomic clone for a lysosomal enzyme gene. The start point of transcription was identified using primer extension of poly(A)+ mRNA. This genomic clone is specific for human alpha-galactosidase A, and it includes sequences for the promoter, complete signal peptide, first exon, and part of the first intron. Direct and inverted repeat elements of 10, 11, 16, 19, and 22 nucleotides (nt) flank the promoter site. A (GA)n repeat element of approx. 60 nt with strong homology to similar elements identified in several species is located upstream from the promoter. A GGGCGG site specific for DNA-binding protein Sp1 is located near a CAAT box, and the CCGCCC inverted repeat of the Sp1 binding sequence is located by the TATA box. The sequence immediately flanking the ATG start codon of the human alpha-galactosidase A is highly homologous to sequences flanking the ATG start codons of the other human lysosomal hydrolases for which sequence information is available (beta-glucocerebrosidase, cathepsin B, cathepsin D, and beta-hexosaminidase alpha chain), but not for any of the other 133 human signal peptides examined. Our analysis also reveals that conversion of the propeptide to the mature enzyme involves cleavage of a C-terminal rather than an N-terminal fragment. This information about the normal alpha-galactosidase A gene will be useful for comparison to data obtained from patients with Fabry disease, who are characterized by a deficiency of this enzyme. This is the first genomic clone described to date for any lysosomal enzyme, and it establishes a reference for future analyses of the molecular events that mediate the expression of this important class of enzymes.

Amino Acid Sequence↗
PubMed2002

A putative iron-regulated TonB-dependent receptor of Mannheimia (Pasteurella) haemolytica A1: possible mechanism for phase variation.

A recombinant plasmid that codes for a novel iron receptor protein (Irp) of Mannheimia (Pasteurella) haemolytica A1 was isolated by the partial complementation of an Escherichia coli fur mutant. The deduced amino acid sequence of Irp exhibited characteristics typical of TonB-dependent receptors. These include: a TonB-box at the N-terminal; a 50 amino acid region homologous to the "plug" domain of the E. coli FhuA and FepA receptors; and a C-terminal TonB-dependent signature which likely functions as an outer membrane anchoring domain. Previously uncharacterized Irp homologues were detected by BLAST analysis of available databases and incomplete microbial genomes. When the irp homologues from Neisseria gonorrhoeae and N. meningitidis were cloned by PCR and expressed in E. coli, novel proteins of the predicted size (84kDa) were detected in cell lysates, demonstrating that these are functional genes. The M. haemolytica A1 irp gene undergoes phase variation at a nucleotide region which contain the sequence AAAAAAATTAAAA (7A-2T-4A) flanked by a short inverted repeat. Site-specific mutagenesis of the 7A-2T-4A sequence as well as replacement of the inverted repeats resulted in a stable construct that expressed the Irp protein without phase variation. The expression of irp in M. haemolytica A1 was regulated by iron concentrations and most likely a Fur homologue, consistent with the proposed function of Irp in iron metabolism. The irp genes may represent contingency loci that play a role in iron acquisition during infection.

Amino Acid Sequence↗
PubMed1992

Promoter elements required for positive control of transcription of the Escherichia coli uhpT gene.

The uhpABCT locus of Escherichia coli encodes the transport system which allows the cell to accumulate a variety of sugar phosphates in unaltered form. The expression of uhpT, the gene encoding the transport protein, is regulated by the uhpABC gene products. The UhpA protein is required for expression; its deduced amino acid sequence shows that it belongs to a subfamily of bacterial transcription regulators including NarL, DegU, and FixJ. Members of this subfamily have an amino-terminal phosphorylation domain characteristic of so-called two-component regulators, such as OmpR, CheY, PhoB, and NtrC, and a carboxyl-terminal domain conserved among many transcriptional activators, including LuxR and MalT. The major sequence elements in the uhpT promoter that are needed for uhpT expression were investigated. Northern (RNA) hybridization analysis showed that the uhpT transcript was only present in cells induced for UhpT transport activity. The start site of transcription was identified by primer extension. Comparison of the regions upstream of the uhpT transcription start site in E. coli and Salmonella typhimurium suggested the presence of four sequence elements that might be involved in promoter function: a typical -10 region, a short inverted repeat centered at -32, a long inverted repeat centered at -64, and a cyclic AMP receptor protein-binding sequence centered at -103. Deletion and linker substitution mutations in the promoter demonstrated that the presence of the cyclic AMP receptor protein-binding site resulted in about an eightfold increase in promoter activity and that the -64, -32, and -10 elements were essential for promoter function. In vivo titration of transcriptional activator UhpA by the intact or mutant promoters on multicopy plasmids identified the -64 element as the UhpA-binding site. The two halves of the -64 inverted repeat did not contribute equally to promoter function and did not have to be intact for UhpA titration. The sequence recognized by UhpA is predicted to be 5' -GGCAAAACNNNGAAA.

Bacterial Proteins↗
PubMed1994

Mapping of Marek's disease virus genome: identification of junction sequences between unique and inverted repeat regions.

Polymerase chain reaction (PCR) to amplify MDV DNA and subsequent sequencing identified the junction of TRL/UL, UL/IRL, IRS/US, and US/TRS. The TRL/UL junction is located 192 bp downstream of the last EcoRI site in the TRL region, while the UL/IRL junction is located 192 bp upstream of the first EcoRI restriction enzyme site in the IRL region. The IRS/US junction is located 950 bp downstream of the second EcoRI site in the IRS region, while the US/TRS junction is located 950 bp upstream of the first EcoRI restriction enzyme site in the TRS region. BamHI restriction enzyme mapping of one of the PCR products identified two novel DNA subfragments, BamHI-U2 and -P4, upstream of the US/TRS junction of the MDV genome. Sequencing of the BamHI-D fragment revealed a novel open reading frame (ORF) encoding a 155 amino acid protein. The TRL/UL junction is located in this ORF. The N-terminal 65 amino acids of this protein is homologous to the N-terminal region of the previously reported pp38, which is located in the UL/IRL region. Computer-assisted analysis indicated that both are transmembrane proteins and that they share an antigenic domain.

Amino Acid Sequence↗
PubMed1996

DNA segments sensitive to single-strand-specific nucleases are present in chromatin of mitotic cells.

It was observed before that DNA in situ in chromatin of mitotic cells is more sensitive to denaturation than DNA in chromatin of interphase cells. DNA sensitivity to denaturation, in these studies, was analyzed by exposing cells to heat or acid and using acridine orange (AO), the metachromatic fluorochrome which can differentially stain double-stranded (ds) vs single-stranded (ss) nucleic acids, as a marker of the degree of DNA denaturation. However, without prior cell treatment with heat or acid no presence of single-stranded DNA in either mitotic or interphase cells was detected by this assay. In the present experiments we demonstrate that DNA in situ in mitotic cells, without any prior treatment that can induce DNA denaturation, is sensitive to ss-specific S1 and mung bean nucleases. Incubation of permeabilized human T cell leukemic MOLT-4, promyelocytic HL-60, histiomonocytic lymphoma U937 cells, or normal PHA-stimulated lymphocytes with S1 or mung bean nucleases generated extensive DNA breakage in mitotic cells. DNA strand breaks were detected using fluorochrome-labeled triphosphonucleotides in the reaction catalyzed by exogenous terminal deoxynucleotidyl transferase. Under identical conditions of the cells' exposure to ss-specific nucleases, DNA breakage in interphase cells was of an order of magnitude less extensive compared to mitotic cells. The data indicate that segments of DNA in mitotic chromosomes, in contrast to interphase cells, may be in a conformation which is sensitive to ss nucleases. This may be a reflection of the differences in the torsional stress of DNA loops between interphase and mitotic chromatin. Namely, greater stress in mitotic loops may lead to formation of the hairpin-loop structures by inverted repeats; such structures are sensitive to ss nucleases. The present method of detection of such segments appears to be more sensitive than the use of AO. The identification of mitotic cells based on sensitivity of their DNA to ss nucleases provides an additional method for their quantification by flow cytometry.

Bromodeoxyuridine↗
PubMedDate not supplied

Tuareg, a novel miniature-inverted repeat family of pearl millet (Pennisetum glaucum) related to the PIF superfamily of maize.

Miniature-inverted repeat transposable elements (MITEs) are abundantly repeated in plant genomes and are especially found in genic regions where they could contribute regulatory elements for gene expression. We describe with molecular and cytological tools the first MITE family reported in pearl millet: Tuareg. It was initially detected in the pearl millet ortholog of Teosinte-branched1, an important developmental gene involved in the domestication of maize. The Tuareg family was amplified recently in the pearl millet genome and elements were found more abundant in wild than in domesticated plants. We found that they shared similarity in their terminal repeats with the previously described mPIF MITEs and that they are also present in other Pennisetum species, in maize and more distantly related grasses. The Tuareg family may be part of MITEs activated by PIF-like transposases and it could have been mobile since pearl millet domestication.

Base Sequence↗
PubMed1989

Genetic variation of African swine fever virus: variable regions near the ends of the viral DNA.

Restriction endonuclease maps of the variable DNA regions of African swine fever virus field isolates from the Iberian peninsula showed that the changes in length are located in the terminal-inverted repetitions and in unique sequences close to the DNA ends. Analysis of nine clones derived from the spleen of an infected pig revealed the existence of frequent length changes within the inverted terminal repetitions. In each clone, changes occurred symmetrically at both terminal-inverted repetitions, suggesting the existence of a terminal-inverted repetition transposition or correction mechanism. Large deletions in unique sequences were detected more frequently in the region located from 8 to 20 kb from the left DNA end. The analysis of this DNA segment from a virulent African swine fever virus isolated in Lisbon (LIS57) showed that this virus strain contains about 8 kb more DNA sequence than the prototype avirulent virus strain (BA71). Hybridization of the additional sequences from LIS57 virus with DNA from different virus field isolates revealed that this DNA region is highly variable in vivo and that it contains several repeated sequences. DNA sequences present around the deletion end points in the variable regions indicate that the deletion process may take place by both homologous and nonhomologous recombination.

African Swine Fever Virus↗
PubMed1992

Cloning, sequencing, and molecular analysis of the groESL operon of Clostridium acetobutylicum.

The groESL operon of Clostridium acetobutylicum was cloned in Escherichia coli by using a gene probe of E. coli groESL. Sequencing of a positively reacting 2.2-kbp HindIII fragment contained in the recombinant plasmid pFN1 and a 2.5-kbp XbaI fragment present in pFN4 revealed that both fragments partially overlapped and together spanned 3,493 bp of the clostridial chromosome. Two complete open reading frames (288 and 1632 bp) were found and identified as the groES- and groEL-homologous genes of C. acetobutylicum, respectively. The 3' end of a third gene (orfZ), which was divergently transcribed, showed no significant homology to other sequences available in the EMBL and GenBank data bases. The length of the groESL-specific mRNA (2.2 kb), a transcription terminator downstream of groEL, and a transcription start site upstream of groES, identified by primer extension analysis, indicated that groES and groEL of C. acetobutylicum are organized in a bicistronic operon. From the transcription start site, the promoter structure 5'-TTGCTA (17 bp) TATTAT that shows high homology to the consensus promoter sequence of gram-positive bacteria as well as E. coli was deduced. Transcription of the groESL operon was strongly heat inducible, and maximum levels of mRNA were detected 15 min after heat shock from 30 to 42 degrees C. An 11-bp inverted repeat, located between promoter and translation start sites of groES and partially identical with similar structures in front of several heat shock genes of other bacteria, may play an important role in the regulation of heat shock gene expression in this organism.

Amino Acid Sequence↗
PubMed1997

Cloning, sequencing and expression of the acylneuraminate lyase gene from Clostridium perfringens A99.

The acylneuraminate lyase gene from Clostridium perfringens A99 was cloned on a 3.3 kb HindIII DNA fragment identified by screening the chromosomal DNA of this species by hybridization with an oligonucleotide probe that had been deduced from the N-terminal amino acid sequence of the purified protein, and another probe directed against a region that is conserved in the acylneuraminate lyase gene of Escherichia coli and in the putative gene of Clostridium tertium. After cloning, three of the recombinant clones expressed lyase activity above the background of the endogenous enzyme of the E. coli host. The sequenced part of the cloned fragment contains the complete acylneuraminate lyase gene (ORF2) of 864 bp that encodes 288 amino acids with a calculated molecular weight of 32.3 kDa. The lyase structural gene follows a noncoding region with an inverted repeat and a ribosome binding site. Upstream from this regulatory region another open reading frame (ORF1) was detected. The 3'-terminus of the lyase structural gene is followed by a further ORF (ORF3). A high homology was found between the amino acid sequences of the sialate lyases from Clostridium perfringens and Haemophilus influenzae (75% identical amino acids) or Trichomonas vaginalis (69% identical amino acids), respectively, whereas the similarity to the gene from E. coli is low (38% identical amino acids). Based on our new sequence data, the 'large' sialidase gene and the lyase gene of C. perfringens are not arranged next to each other on the chromosome of this species.

Amino Acid Sequence↗
PubMed1986

Nucleotide sequences of the R1-19 plasmid transfer genes traM, finP, traJ, and traY and the traYZ promoter.

The complete nucleotide sequences of the R1 drd-19 (R1-19) plasmid transfer genes traM, finP, traJ, and traY and the region encoding the traYZ promoter were determined. The traM protein from R1-19 was similar to the 127-amino-acid traM product from the conjugative plasmid F; only 28 residues were not identical. finP, a negative regulatory element of the traJ gene, contained a 12-base-pair inverted repeat identical to that found in the F plasmid, but differed in the 7 base pairs found between the repeats. The traJ gene and the traYZ promoter (the site of transcriptional stimulation by the traJ product) were completely different from the equivalent sequences in plasmid F. Galactokinase fusion studies of the traYZ promoter indicated that the R1-19 and F plasmids have analogous but not homologous traYZ promoter strengths and regulation. The traY protein from R1-19 was 44 residues shorter than the traY product from plasmid F, but there was some homology within the C-terminal halves of the traY gene products. The predicted translational start codon for the traY gene is GUG.

Alleles↗
PubMed1993

The complete nucleotide sequence of a small cryptic plasmid from a rumen bacterium of the genus Butyrivibrio.

The complete nucleotide sequence of a plasmid, designated pRJF1, isolated from a rumen bacterium of the genus Butyrivibrio, has been determined. pRJF1 is a small plasmid (2631 bp) which shows the high AT content (64%) typical of plasmids from gram-positive organisms. Computer analysis of sequence data revealed two major open reading frames encoded on the same strand but in different frames. The smaller, ORF1 (435 bp), is preceded by Shine Dalgarno (SD) and Escherichia coli-10, -35 sequences and is predicted to encode an acidic polypeptide of 145 aa. The putative protein shows little homology to known bacterial proteins except in a small region similar to part of the Pre protein (plasmid recombination enzyme) of Bacillus plasmid pTB913. Pre proteins of the pTB913 family, however, show conservation of several amino acids in the amino terminal region of the protein that may be related to function. This pattern of amino acid conservation is not observed in ORF1. The predicted product of ORF2 (849 bp) is a basic protein of 283 as that shows significant similarity to repA gene products of plasmids from gram-negative (but not gram-positive) bacteria. No typical Shine Dalgarno sequence or -10, -35 sequences precede this coding region. While sequence homologous to nick sites of plasmids from gram-positive organisms that replicate via ssDNA intermediates were also detected in pRJF1, the order of the three consecutive inverted repeats typical of nick sites is not conserved. pRJF1, however, does contain an extended region of directly and inversely repeated sequence motifs reminiscent of theta replication origins.

Amino Acid Sequence↗
PubMed2002

Characterization of Chelonus inanitus polydnavirus segments: sequences and analysis, excision site and demonstration of clustering.

Polydnaviruses (genera Ichnovirus and Bracovirus) have a segmented genome of circular double-stranded DNA molecules, replicate in the ovary of parasitic wasps and are essential for successful parasitism of the host. Here we show the first detailed analysis of various segments of a bracovirus, the Chelonus inanitus virus (CiV). Four segments were sequenced and two of them, CiV12 and CiV14, were found to be closely related while CiV14.5 and CiV16.8 were unrelated. CiV12, CiV14.5 and CiV16.8 are unique while CiV14 occurs also nested in another larger segment. All four segments are predicted to contain genes and predictions could be substantiated in most cases. Comparison with databases revealed no significant similarities at either the nucleotide or amino acid level. Inverted repeats with identities between 77% and 92% and lengths between 26 bp and 100 bp were found on all segments outside of predicted genes. Hybridization experiments indicate that CiV12 and CiV14 are both flanked by other virus segments, suggesting that proviral CiV segments are clustered in the genome of the wasp. The integration/excision site of CiV14 was analysed and compared to that of CiV12. On both termini of proviral CiV12 and CiV14 as well as in the excised circular molecule and the rejoined DNA a very similar repeat of 14 bp was found. A model to illustrate where the terminal repeats might recombine to yield the circular molecule is presented. Excision of CiV12 and CiV14 is restricted to the female and sets in at a very specific time-point in pupal-adult development.

Animals↗
PubMed1996

A chloroplast transcript lacking the 3' inverted repeat is degraded by 3'-->5' exoribonuclease activity.

Chlamydomonas reinhardtii strains harboring deletions of the chloroplast atpB 3' inverted repeat (IR) are weakly phototrophic due to reduced accumulation of discrete atpB transcripts and the chloroplast ATPase beta-subunit protein. A sequence of 18 guanosine residues, which can impede a 3'-->5' exoribonuclease in vitro, is able to substitute for the atpB IR in vivo. Strains containing the poly-guanosine tract in place of the atpB 3' IR are phototrophic and accumulate near wild-type levels of discrete atpB transcripts and the ATPase beta-subunit protein. Because these atpB transcripts contain the 18 guanosine residues, and the poly-guanosine tract is not a terminator of transcription, the accumulation of discrete atpB transcripts is likely the result of impediment of 3'-->5' exoribonuclease activity. These findings support a model in which atpB transcripts lacking the 3' IR are degraded by 3'-->5' exoribonuclease activity, and demonstrate that the poly-guanosine tract can be used to study chloroplast RNA metabolism in vivo.

Adenosine Triphosphatases↗
PubMed1995

Homologous recombination as the main mechanism for DNA integration and cause of rearrangements in the filamentous ascomycete Ashbya gossypii.

A slow and a fast growth phenotype were observed after transformation of the phytopathogenic fungus Ashbya gossypii using a plasmid carrying homologous DNA and as selectable marker the Tn903 aminoglycoside resistance gene expressed from a strong A. gossypii promoter. Transformations with circular plasmids yielded slowly and irregularly growing geneticin-resistant mycelia in which 1% of nuclei contained plasmid sequences. Occasionally, fast growing sectors appeared which were shown to be initiated by homologous integration of the transforming DNA. Transformants obtained with plasmids linearized within the homology region immediately exhibited fast radial growth. In all 28 transformants analyzed plasmid DNA was integrated homologously. Such apparent lack of nonhomologous recombination has so far not been observed in filamentous ascomycetes. In 14 transformants two to four tandemly integrated plasmid copies were found. They underwent several types of genetic changes, mainly in the older mycelium: excision of whole plasmid copies and rearrangements within the integrated DNA (inversions and deletions). These internal rearrangements involved 360-bp inverted repeats, remnants of IS-elements flanking the resistance gene, and 156-bp direct repeats, originating from the strong A. gossypii promoter. Improved vectors lacking sequence repetitions were constructed and used for stable one-step gene replacement in A. gossypii.

Aminoglycosides↗
PubMed1999

Production of aberrant promoter transcripts contributes to methylation and silencing of unlinked homologous promoters in trans.

Previous work has suggested that de novo methylation of plant nuclear genes can be triggered by an RNA-DNA interaction. To test whether transcription of a promoter would induce de novo methylation and silencing of unlinked genes driven by the same promoter, a chimeric 'gene' consisting of a nopaline synthase promoter (NOSpro) positioned downstream of the cauliflower mosaic virus 35S promoter (35Spro) and flanked at the 3' end by a NOS terminator (NOSter) was constructed and introduced into the genome of a plant that normally expresses an unmethylated NOSpro-neomycinphosphotransferase (nptII) gene. Transformants were tested for kanamycin resistance and NOSpro RNA synthesis. Most produced a full-length polyadenylated NOSpro RNA, which did not induce silencing or methylation at the NOSpro-nptII target gene. One, however, contained truncated non-polyadenylated NOSpro RNA; in this plant, the NOSpro-nptII gene became silenced and methylated in the NOSpro region. Molecular analysis of the NOSpro silencing locus revealed two incomplete copies of the 35Spro-NOSpro gene arranged as an inverted repeat with NOSpro sequences at the center. Reducing NOSpro transcription by crossing a 35Spro-silencing locus partially reactivated nptII gene expression and decreased NOSpro methylation at the target locus, thus implicating aberrant NOSpro RNA in this trans-silencing phenomenon.

Amino Acid Oxidoreductases↗
PubMed1986

Sequence analysis of the Bacillus subtilis argC promoter region.

A previously characterised promoter region upstream from the Bacillus subtilis argC gene was sequenced. The in vivo position of transcription start point (+1), was determined by mung-bean-nuclease mapping. The nucleotide (nt) sequences in the '-10' (TATAAT) and '-35' (TTGAAT) regions closely resemble consensus promoter sequences recognised by B. subtilis sigma 43 and Escherichia coli sigma 70 RNA polymerases. Between +9 and -64 are three imperfect inverted repeats with high homology to the E. coli arginine biosynthetic gene putative operator sequences (ARG boxes) [Cunin et al., Nucl. Acids Res. II (1985) 5007-5019] and which contain variable intra-repeat distances. Upstream from the '-35' region, extending as far as -71, is a 97% AT-rich sequence. The argC mRNA has a short leader region containing a B. subtilis ribosome-binding site 8 nt upstream from a TTG start codon for an open reading frame (ORF). The deduced amino acid sequence for this ORF contains regions of homology to that for the E. coli argC N-terminal region.

Arginine↗
PubMed1994

Gene structure of the 'large' sialidase isoenzyme from Clostridium perfringens A99 and its relationship with other clostridial nanH proteins.

Clostridium perfringens possesses two sialidase isoenzymes of different molecular weight. Almost 90% of the gene encoding the 'large' form was found on a 3.1 kb chromosomal fragment (Sau3AI) of strain A99 by hybridization with probes developed from the N-terminal protein sequence and from commonly conserved sialidase motifs ('Asp-boxes'), whereas the remaining 3'-terminal part was detected on a 2.1 kb fragment (Hind III) of chromosomal DNA. After combination of both fragments, the resulting E. coli clones expressed sialidase activity, the properties of the recombinant sialidase corresponding with those of the wild type enzyme. The entire chromosomal fragment of 3665 bp encompasses the complete sialidase gene of 2082 bp corresponding to 694 amino acids, from which a molecular weight of 72,956 for the mature protein can be deduced. The first 41 amino acids are mostly hydrophobic and probably represent a signal peptide. The sialidase structural gene follows a non-coding region with an inverted repeat and a ribosome-binding site. Upstream from the regulatory region, another open reading frame (ORF) was detected. The 3'-terminus of the sialidase structural gene is directly followed by a further ORF of unknown function, which possibly encodes a putative permease or the acylneuraminate pyruvate-lyase involved in sialic acid catabolism. The primary structure of the 'large' isoenzyme is very similar to the sialidase of Clostridium septicum (55% identical amino acids), whereas the homology with the 'small' form of the same species is comparatively low (26%).

Amino Acid Sequence↗
PubMed1993

A second groEL-like gene, organized in a groESL operon is present in the genome of Synechocystis sp. PCC 6803.

Using a groEL gene of Synechococcus sp. PCC 7942 as a DNA probe, a 4.8-kilobase pair (kbp) BamHI fragment of chromosomal DNA of Synechocystis sp. PCC 6803 was cloned. Sequencing of 3.25 kbp of the BamHI fragment revealed three open reading frames. The amino acid sequences deduced from the nucleotide sequences of the two open reading frames are identical to those gained from N-terminal sequencing of purified groEL and groES proteins. This finding demonstrates that these two open reading frames correspond to groEL and groES genes of Synechocystis sp. PCC 6803. groEL of Synechocystis sp. PCC 6803 is remarkably homologous to groEL proteins of other organisms. Southern blot analysis indicates that only one groESL operon is present in the genomic DNA of Synechocystis sp. PCC 6803, whereas the existence of at least two copies of groEL-analogous genes are anticipated. The level of the bicistronic, 2.2-kb transcript of groESL operon increased 100-fold within 15 min upon heat stress. A 9-base pair inverted repeat revealed around the groESL promoter might be involved in regulation of the heat shock response.

Amino Acid Sequence↗