The adenosine2 gene of Drosophila melanogaster encodes a formylglycineamide ribotide amidotransferase

Genome ◽  
1993 ◽  
Vol 36 (5) ◽  
pp. 924-934 ◽  
Author(s):  
S. Y. K. Tiong ◽  
D. Nash
Keyword(s):  
Drosophila Melanogaster ◽  
Amino Acid ◽  
Genomic Dna ◽  
Gene Rearrangement ◽  
Single Gene ◽  
Genetic Material ◽  
Biosynthetic Enzyme ◽  
E Coli ◽  
Enzymatic Function ◽  
Rearrangement Breakpoint

Drosophila melanogaster genomic DNA spanning an adenosine2 gene rearrangement breakpoint (in cytological map region 26B1-2) was cloned and a composite ade2 base sequence was derived from this DNA and from a corresponding cDNA. Based on genetic evidence, the ade2 gene is thought to encode the purine biosynthetic enzyme formylglycineamide ribotide amidotransferase (FGARAT). The cDNA hybridizes to a 4.8-kb message that encodes a 1354 amino acid polypeptide with extensive similarity to Escherichia coli FGARAT. The D. melanogaster FGARAT amino acid sequence is considerably more like that of the E. coli enzyme than is the FGARAT of B. subtilis, which has two polypeptides with, collectively, 969 amino acids. It is suggested that the taxonomically anomalous similarity between the eukaryotic FGARAT and that from E. coli may indicate horizontal exchange of genetic material. On the basis of substantially greater conservation of sequences snared by all three species compared with those present only in E. coli and D. melanogaster, we suggest that no radical alteration of enzymatic function accompanied the transition between the single-gene and the two-gene state.Key words: Drosophila melanogaster, purine biosynthesis genes, formylglycineamide ribotide amidotransferase, formylglycineamidine ribotide synthase, adenosine2 locus, horizontal gene transfer.

scholarly journals Isolation and Characterization of vicH, Encoding a New Pleiotropic Regulator in Vibrio cholerae

2000 ◽  
Vol 182 (7) ◽  
pp. 2026-2032 ◽  
Author(s):  
Christian Tendeng ◽  
Cyril Badaut ◽  
Evelyne Krin ◽  
Pierre Gounon ◽  
Saravuth Ngo ◽  
...  
Keyword(s):  
Amino Acid ◽  
Vibrio Cholerae ◽  
Genomic Library ◽  
Single Gene ◽  
Wild Type ◽  
Semisolid Medium ◽  
E Coli ◽  
Isolation And Characterization ◽  
Serovar Typhimurium

ABSTRACT During the last decade, the hns gene and its product, the H-NS protein, have been extensively studied in Escherichia coli. H-NS-like proteins seem to be widespread in gram-negative bacteria. However, unlike in E. coli and inSalmonella enterica serovar Typhimurium, little is known about their role in the physiology of those organisms. In this report, we describe the isolation of vicH, an hns-like gene in Vibrio cholerae, the etiological agent of cholera. This gene was isolated from a V. cholerae genomic library by complementation of different phenotypes associated with anhns mutation in E. coli. It encodes a 135-amino-acid protein showing approximately 50% identity with both H-NS and StpA in E. coli. Despite a low amino acid conservation in the N-terminal part, VicH is able to cross-react with anti-H-NS antibodies and to form oligomers in vitro. ThevicH gene is expressed as a single gene from two promoters in tandem and is induced by cold shock. A V. choleraewild-type strain expressing a vicHΔ92 gene lacking its 3′ end shows pleiotropic alterations with regard to mucoidy and salicin metabolism. Moreover, this strain is unable to swarm on semisolid medium. Similarly, overexpression of the vicH wild-type gene results in an alteration of swarming behavior. This suggests that VicH could be involved in the virulence process in V. cholerae, in particular by affecting flagellum biosynthesis.

scholarly journals Characterization of the Avian PathogenicEscherichia coli Hemagglutinin Tsh, a Member of the Immunoglobulin A Protease-Type Family of Autotransporters

1999 ◽  
Vol 67 (2) ◽  
pp. 772-781 ◽  
Author(s):  
Christos Stathopoulos ◽  
David L. Provence ◽  
Roy Curtiss
Keyword(s):  
Amino Acid ◽  
Sequence Data ◽  
Single Gene ◽  
Shigella Flexneri ◽  
Immunoglobulin A ◽  
Site Directed Mutagenesis ◽  
Bacterial Cells ◽  
E Coli ◽  
K 12

ABSTRACT We reported earlier that a single gene, tsh, isolated from a strain of avian pathogenic Escherichia coli (APEC) was sufficient to confer on E. coli K-12 a hemagglutinin-positive phenotype and that the deduced sequence of the Tsh protein shared homology to the serine-type immunoglobulin A (IgA) proteases of Neisseria gonorrhoeae and Haemophilus influenzae. In this report we show that E. coli K-12 containing the recombinant tsh gene produced two proteins, a 106-kDa extracellular protein and a 33-kDa outer membrane protein, and was also able to agglutinate chicken erythrocytes. N-terminal sequence data indicated that the 106-kDa protein, designated Tshs, was derived from the N-terminal end of Tsh after the removal of a 52-amino-acid N-terminal signal peptide, while the 33-kDa protein, designated Tshβ, was derived from the C-terminal end of Tsh starting at residue N1101. The Tshsdomain contains the 7-amino-acid serine protease motif that includes the active-site serine (S259), found also in the secreted domains of the IgA proteases. However, site-directed mutagenesis of S259 did not abolish the hemagglutinin activity or the extracellular secretion of Tshs indicating that host-directed proteolysis was mediating the release of Tshs. Studies with an E. coli K-12ompT mutant strain showed that the surface protease OmpT was not needed for the secretion of Tshs. Tsh belongs to a subclass of the IgA protease family, which also includes EspC of enteropathogenic E. coli, EspP of enterohemorragic E. coli, and SepA and VirG of Shigella flexneri, which seem to involve a host endopeptidase to achieve extracellular release of their N-terminal domains. In proteolytic studies conducted in vitro, Tshs did not cleave the substrate of the IgA proteases, human IgA1 or chicken IgA, and did not show proteolytic activity in a casein-based assay. Correlation of Tsh expression and hemagglutination activity appears to be a very complex phenomenon, influenced by strain and environmental conditions. Nevertheless, for both APEC and recombinant E. coli K-12 strains containing thetsh gene, it was only the whole bacterial cells and not the cell-free supernatants that could confer hemagglutinin activity. Our results provide insights into the expression, secretion, and proteolytic features of the Tsh protein, which belongs to the growing family of gram-negative bacterial extracellular virulence factors, named autotransporters, which utilize a self-mediated mechanism to achieve export across the bacterial cell envelope.

scholarly journals The Drosophila melanogaster ade5 Gene Encodes a Bifunctional Enzyme for Two Steps in the de novo Purine Synthesis Pathway

Genetics ◽  
2000 ◽  
Vol 154 (3) ◽  
pp. 1239-1253
Author(s):  
Allyson F O'Donnell ◽  
Stanley Tiong ◽  
David Nash ◽  
Denise V Clark
Keyword(s):  
Drosophila Melanogaster ◽  
De Novo ◽  
Single Gene ◽  
Hybrid Dysgenesis ◽  
Induced Mutations ◽  
Gene Encoding ◽  
Purine Synthesis ◽  
E Coli ◽  
Gene Maps

Abstract Steps 6 and 7 of de novo purine synthesis are performed by 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-[(N-succinylamino)carbonyl]-5-aminoimidazole ribonucleotide synthetase (SAICARs), respectively. In vertebrates, a single gene encodes AIRc-SAICARs with domains homologous to Escherichia coli PurE and PurC. We have isolated an AIRc-SAICARs cDNA from Drosophila melanogaster via functional complementation with an E. coli purC purine auxotroph. This cDNA encodes AIRc yet is unable to complement an E. coli purE mutant, suggesting functional differences between Drosophila and E. coli AIRc. In vertebrates, the AIRc-SAICARs gene shares a promoter region with the gene encoding phosphoribosylamidotransferase, which performs the first step in de novo purine synthesis. In Drosophila, the AIRc-SAICARs gene maps to section 11B4-14 of the X chromosome, while the phosphoribosylamidotransferase gene (Prat) maps to chromosome 3; thus, the close linkage of these two genes is not conserved in flies. Three EMS-induced X-linked adenine auxotrophic mutations, ade41, ade51, and ade52, were isolated. Two gammaradiation-induced (ade53 and ade54) and three hybrid dysgenesis-induced (ade55, ade56, and ade58) alleles were also isolated. Characterization of the auxotrophy and the finding that the hybrid dysgenesis-induced mutations all harbor P transposon sequences within the AIRc-SAICARs gene show that ade5 encodes AIRc-SAICARs.

Paris I Dysfibrinogenemia: A Point Mutation in Intron 8 Results in Insertion of a 15 Amino Acid Sequence in the Fibrinogen γ-Chain

1993 ◽  
Vol 69 (03) ◽  
pp. 217-220 ◽  
Author(s):  
Jonathan B Rosenberg ◽  
Peter J Newman ◽  
Michael W Mosesson ◽  
Marie-Claude Guillin ◽  
David L Amrani
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Point Mutation ◽  
Genomic Dna ◽  
Comparative Sequence Analysis ◽  
Chain Gene ◽  
Molecular Defect ◽  
Nucleotide Position ◽  
Normal Individuals ◽  
Polymerase Chain

SummaryParis I dysfibrinogenemia results in the production of a fibrinogen molecule containing a functionally abnormal γ-chain. We determined the basis of the molecular defect using polymerase chain reaction (PCR) to amplify the γ-chain region of the Paris I subject’s genomic DNA. Comparative sequence analysis of cloned PCR segments of normal and Paris I genomic DNA revealed only an A→G point mutation occurring at nucleotide position 6588 within intron 8 of the Paris I γ-chain gene. We examined six normal individuals and found only normal sequence in this region, indicating that this change is not likely to represent a normal polymorphism. This nucleotide change leads to a 45 bp fragment being inserted between exons 8 and 9 in the mature γparis I chain mRNA, and encodes a 15 amino acid insert after γ350 [M-C-G-E-A-L-P-M-L-K-D-P-C-Y]. Alternative splicing of this region from intron 8 into the mature Paris I γ-chain mRNA also results after translation into a substitution of S for G at position γ351. Biochemical studies of 14C-iodoacetamide incorporation into disulfide-reduced Paris I and normal fibrinogen corroborated the molecular biologic predictions that two additional cysteine residues exist within the γpariS I chain. We conclude that the insertion of this amino acid sequence leads to a conformationallyaltered, and dysfunctional γ-chain in Paris I fibrinogen.

scholarly journals Tailoring a Global Iron Regulon to a Uropathogen

mBio ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Rajdeep Banerjee ◽  
Erin Weisenhorn ◽  
Kevin J. Schwartz ◽  
Kevin S. Myers ◽  
Jeremy D. Glasner ◽  
...  
Keyword(s):  
Amino Acids ◽  
Urinary Tract ◽  
Amino Acid ◽  
Regulatory Network ◽  
Iron Homeostasis ◽  
Iron Limitation ◽  
Content Type ◽  
E Coli ◽  
General Stress ◽  
K 12

ABSTRACT Pathogenicity islands and plasmids bear genes for pathogenesis of various Escherichia coli pathotypes. Although there is a basic understanding of the contribution of these virulence factors to disease, less is known about variation in regulatory networks in determining disease phenotypes. Here, we dissected a regulatory network directed by the conserved iron homeostasis regulator, ferric uptake regulator (Fur), in uropathogenic E. coli (UPEC) strain CFT073. Comparing anaerobic genome-scale Fur DNA binding with Fur-dependent transcript expression and protein levels of the uropathogen to that of commensal E. coli K-12 strain MG1655 showed that the Fur regulon of the core genome is conserved but also includes genes within the pathogenicity/genetic islands. Unexpectedly, regulons indicative of amino acid limitation and the general stress response were also indirectly activated in the uropathogen fur mutant, suggesting that induction of the Fur regulon increases amino acid demand. Using RpoS levels as a proxy, addition of amino acids mitigated the stress. In addition, iron chelation increased RpoS to the same levels as in the fur mutant. The increased amino acid demand of the fur mutant or iron chelated cells was exacerbated by aerobic conditions, which could be partly explained by the O2-dependent synthesis of the siderophore aerobactin, encoded by an operon within a pathogenicity island. Taken together, these data suggest that in the iron-poor environment of the urinary tract, amino acid availability could play a role in the proliferation of this uropathogen, particularly if there is sufficient O2 to produce aerobactin. IMPORTANCE Host iron restriction is a common mechanism for limiting the growth of pathogens. We compared the regulatory network controlled by Fur in uropathogenic E. coli (UPEC) to that of nonpathogenic E. coli K-12 to uncover strategies that pathogenic bacteria use to overcome iron limitation. Although iron homeostasis functions were regulated by Fur in the uropathogen as expected, a surprising finding was the activation of the stringent and general stress responses in the uropathogen fur mutant, which was rescued by amino acid addition. This coordinated global response could be important in controlling growth and survival under nutrient-limiting conditions and during transitions from the nutrient-rich environment of the lower gastrointestinal (GI) tract to the more restrictive environment of the urinary tract. The coupling of the response of iron limitation to increased demand for amino acids could be a critical attribute that sets UPEC apart from other E. coli pathotypes.

scholarly journals A Cluster of Cuticle Protein Genes of Drosophila melanogaster at 65A: Sequence, Structure and Evolution

Genetics ◽  
1997 ◽  
Vol 147 (3) ◽  
pp. 1213-1224
Author(s):  
Jean-Philippe Charles ◽  
Carol Chihara ◽  
Shamim Nejad ◽  
Lynn M Riddiford
Keyword(s):  
Drosophila Melanogaster ◽  
Genomic Dna ◽  
Multiple Copy ◽  
Sequence Structure ◽  
Coding Regions ◽  
The Third ◽  
Genetic Complexity ◽  
Genes Encoding ◽  
Cuticle Protein ◽  
Cuticle Proteins

A 36-kb genomic DNA segment of the Drosophila melanogaster genome containing 12 clustered cuticle genes has been mapped and partially sequenced. The cluster maps at 65A 5-6 on the left arm of the third chromosome, in agreement with the previously determined location of a putative cluster encompassing the genes for the third instar larval cuticle proteins LCP5, LCP6 and LCP8. This cluster is the largest cuticle gene cluster discovered to date and shows a number of surprising features that explain in part the genetic complexity of the LCP5, LCP6 and LCP8 loci. The genes encoding LCP5 and LCP8 are multiple copy genes and the presence of extensive similarity in their coding regions gives the first evidence for gene conversion in cuticle genes. In addition, five genes in the cluster are intronless. Four of these five have arisen by retroposition. The other genes in the cluster have a single intron located at an unusual location for insect cuticle genes.

scholarly journals Antimicrobial activity of Syzygium aromaticum L. essential oil on extended-spectrum beta-lactamases-producing Escherichia coli

2020 ◽  
Vol 44 (1) ◽  
Author(s):  
E. L. Mejía-Argueta ◽  
J. G. Santillán-Benítez ◽  
M. M. Canales-Martinez ◽  
A. Mendoza-Medellín
Keyword(s):  
Escherichia Coli ◽  
Essential Oil ◽  
Genetic Material ◽  
Gastrointestinal Diseases ◽  
Syzygium Aromaticum ◽  
Antibiotic Resistant ◽  
Plant Essential Oils ◽  
E Coli ◽  
Extended Spectrum ◽  
Tract Infections

Abstract Background To test the antimicrobial potential of clove essential oil that has been less investigated on antimicrobial-resistant organisms (extended-spectrum β-lactamase-ESBL-producing Escherichia coli), we collected 135 ESBL-producing Escherichia coli strains given that E. coli is the major organism increasingly isolated as a cause of complicated urinary and gastrointestinal tract infections, which remains an important cause of therapy failure with antibiotics for the medical sector. Then, in this study, we evaluated the relationship between the antibacterial potential activity of Syzygium aromaticum essential oil (EOSA) and the expression of antibiotic-resistant genes (SHV-2, TEM-20) in plasmidic DNA on ESBL-producing E. coli using RT-PCR technique. Results EOSA was obtained by hydrodistillation. Using Kirby-Baüer method, we found that EOSA presented a smaller media (mean = 15.59 mm) in comparison with chloramphenicol (mean = 17.73 mm). Thus, there were significant differences (p < 0.0001). Furthermore, EOSA had an antibacterial activity, particularly on ECB132 (MIC: 10.0 mg/mL and MBC: 80.0 mg/mL), and a bacteriostatic effect by bactericidal kinetic. We found that the expression of antibiotic-resistant gene blaTEM-20 was 23.52% (4/17 strains) and no expression of blaSHV-2. EOSA presented such as majority compounds (eugenol, caryophyllene) using the GC–MS technique. Conclusions Plant essential oils and their active ingredients have potentially high bioactivity against a different target (membranes, cytoplasm, genetic material). In this research, EOSA might become an important adjuvant against urinary and gastrointestinal diseases caused by ESBL-producing E. coli.

scholarly journals Global versus Local Regulatory Roles for Lrp-Related Proteins: Haemophilus influenzae as a Case Study

2001 ◽  
Vol 183 (13) ◽  
pp. 4004-4011 ◽  
Author(s):  
Devorah Friedberg ◽  
Michael Midkiff ◽  
Joseph M. Calvo
Keyword(s):  
Amino Acid ◽  
Haemophilus Influenzae ◽  
Regulatory Protein ◽  
Enteric Bacteria ◽  
Regulatory Role ◽  
Regulatory Function ◽  
Ecological Niches ◽  
E Coli ◽  
Sequence Identity ◽  
Related Proteins

ABSTRACT Lrp (leucine-responsive regulatory protein) plays a global regulatory role in Escherichia coli, affecting expression of dozens of operons. Numerous lrp-related genes have been identified in different bacteria and archaea, includingasnC, an E. coli gene that was the first reported member of this family. Pairwise comparisons of amino acid sequences of the corresponding proteins shows an average sequence identity of only 29% for the vast majority of comparisons. By contrast, Lrp-related proteins from enteric bacteria show more than 97% amino acid identity. Is the global regulatory role associated withE. coli Lrp limited to enteric bacteria? To probe this question we investigated LrfB, an Lrp-related protein fromHaemophilus influenzae that shares 75% sequence identity with E. coli Lrp (highest sequence identity among 42 sequences compared). A strain of H. influenzae having anlrfB null allele grew at the wild-type growth rate but with a filamentous morphology. A comparison of two-dimensional (2D) electrophoretic patterns of proteins from parent and mutant strains showed only two differences (comparable studies withlrp + and lrp E. coli strains by others showed 20 differences). The abundance of LrfB in H. influenzae, estimated by Western blotting experiments, was about 130 dimers per cell (compared to 3,000 dimers per E. colicell). LrfB expressed in E. coli replaced Lrp as a repressor of the lrp gene but acted only to a limited extent as an activator of the ilvIH operon. Thus, although LrfB resembles Lrp sufficiently to perform some of its functions, its low abundance is consonant with a more local role in regulating but a few genes, a view consistent with the results of the 2D electrophoretic analysis. We speculate that an Lrp having a global regulatory role evolved to help enteric bacteria adapt to their ecological niches and that it is unlikely that Lrp-related proteins in other organisms have a broad regulatory function.

scholarly journals Roles of the C-Terminal Amino Acids of Non-Hexameric Helicases: Insights from Escherichia coli UvrD

2021 ◽  
Vol 22 (3) ◽  
pp. 1018
Author(s):  
Hiroaki Yokota
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Single Molecule ◽  
Underlying Mechanism ◽  
Amino Acid Sequences ◽  
E Coli ◽  
X Ray Crystallography ◽  
Terminal Amino

Helicases are nucleic acid-unwinding enzymes that are involved in the maintenance of genome integrity. Several parts of the amino acid sequences of helicases are very similar, and these quite well-conserved amino acid sequences are termed “helicase motifs”. Previous studies by X-ray crystallography and single-molecule measurements have suggested a common underlying mechanism for their function. These studies indicate the role of the helicase motifs in unwinding nucleic acids. In contrast, the sequence and length of the C-terminal amino acids of helicases are highly variable. In this paper, I review past and recent studies that proposed helicase mechanisms and studies that investigated the roles of the C-terminal amino acids on helicase and dimerization activities, primarily on the non-hexermeric Escherichia coli (E. coli) UvrD helicase. Then, I center on my recent study of single-molecule direct visualization of a UvrD mutant lacking the C-terminal 40 amino acids (UvrDΔ40C) used in studies proposing the monomer helicase model. The study demonstrated that multiple UvrDΔ40C molecules jointly participated in DNA unwinding, presumably by forming an oligomer. Thus, the single-molecule observation addressed how the C-terminal amino acids affect the number of helicases bound to DNA, oligomerization, and unwinding activity, which can be applied to other helicases.

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