scholarly journals Characterisation and functional analysis of canine TLR5

2020 ◽  
Vol 26 (6) ◽  
pp. 451-458
Author(s):  
Aihua Zhu ◽  
Lingling Wei ◽  
Sujuan Hu ◽  
Cheng Yang ◽  
Caifa Chen ◽  
...  

In this study, we characterised the single exon TLR5 gene of the Chinese rural dog. Sequence analysis revealed a 2577 nucleotide-long open reading frame of canine TLR5, encoding an 858 amino acid-long protein. The putative amino acid sequence of canine TLR5 consisted of a signal peptide sequence, 15 LRR domains, a LRR C-terminal domain, a transmembrane domain and an intracellular Toll-IL-1 receptor domain. The amino acid sequence of the canine TLR5 protein shared 95.4% identity with vulpine, 72.2% with feline and 64.7% with human TLR5. Plasmids expressing canine TLR5 and NF-κB-luciferase were constructed and transfected into HEK293T cells. Expression was confirmed by indirect immunofluorescence assay. These HEK293T cells transfected with the canine TLR5- and NF-κB-luciferase plasmids significantly responded to flagellin from Salmonella enteritidis serovar Typhimurium, indicating that it is a functional TLR5 homolog. In response to stimulation with Salmonella enteritidis, the level of TLR5 mRNA significantly increased over the control in PBMCs at 4 h. The levels of IL-8, IL-6 and IL-1β also increased after exposure. The highest levels of TLR5, IL-8 and IL-1β expression were detected at 8, 4 and 12 h after stimulation, respectively. These results imply that the expression of canine TLR5 may participate in the immune response against bacterial pathogens.

2001 ◽  
Vol 67 (2) ◽  
pp. 713-720 ◽  
Author(s):  
Wataru Hashimoto ◽  
Hikaru Miki ◽  
Noriaki Tsuchiya ◽  
Hirokazu Nankai ◽  
Kousaku Murata

ABSTRACT When grown on xanthan as a carbon source, the bacteriumBacillus sp. strain GL1 produces extracellular xanthan lyase (75 kDa), catalyzing the first step of xanthan depolymerization (H. Nankai, W. Hashimoto, H. Miki, S. Kawai, and K. Murata, Appl. Environ. Microbiol. 65:2520–2526, 1999). A gene for the lyase was cloned, and its nucleotide sequence was determined. The gene contained an open reading frame consisting of 2,793 bp coding for a polypeptide with a molecular weight of 99,308. The polypeptide had a signal peptide (2 kDa) consisting of 25 amino acid residues preceding the N-terminal amino acid sequence of the enzyme and exhibited significant homology with hyaluronidase of Streptomyces griseus(identity score, 37.7%). Escherichia coli transformed with the gene without the signal peptide sequence showed a xanthan lyase activity and produced intracellularly a large amount of the enzyme (400 mg/liter of culture) with a molecular mass of 97 kDa. During storage at 4°C, the purified enzyme (97 kDa) from E. coli was converted to a low-molecular-mass (75-kDa) enzyme with properties closely similar to those of the enzyme (75 kDa) fromBacillus sp. strain GL1, specifically in optimum pH and temperature for activity, substrate specificity, and mode of action. Logarithmically growing cells of Bacillus sp. strain GL1 on the medium with xanthan were also found to secrete not only xanthan lyase (75 kDa) but also a 97-kDa protein with the same N-terminal amino acid sequence as that of xanthan lyase (75 kDa). These results suggest that, in Bacillus sp. strain GL1, xanthan lyase is first synthesized as a preproform (99 kDa), secreted as a precursor (97 kDa) by a signal peptide-dependent mechanism, and then processed into a mature form (75 kDa) through excision of a C-terminal protein fragment with a molecular mass of 22 kDa.


2000 ◽  
Vol 66 (6) ◽  
pp. 2325-2329 ◽  
Author(s):  
Myrta W. Atiles ◽  
Edward G. Dudley ◽  
James L. Steele

ABSTRACT A branched-chain aminotransferase gene (ilvE) fromLactococcus lactis LM0230 was identified on a 9-kb chromosomal insert by complementation in Escherichia coliDL39. Sequencing of a 2.0-kbp fragment resulted in the identification of a 1,023-bp open reading frame that could encode a 340-amino-acid protein. Sequence analysis of the deduced amino acid sequence revealed 62% identity to IlvE of Haemophilus influenzae and high similarity to IlvEs from a variety of organisms found in GenBank classified as class IV aminotransferases. Under logarithmic growth in complex medium, ilvE is transcribed monocistronically as a 1.1-kb transcript. Hydrophobicity plot analysis of the deduced amino acid sequence and the lack of a signal peptide sequence suggest IlvE is a cytosolic protein. A derivative of LM0230 lacking IlvE activity was constructed by gene replacement. Comparison of the IlvE-deficient strain's ability to grow in defined media lacking an amino acid but containing its α-keto acid biosynthetic precursor to that of the wild-type strain indicated that IlvE is the only enzyme capable of synthesis of Ile and Val from their biosynthetic precursors. Comparison of the aminotransferase activity of the IlvE mutant to LM0230 revealed that the mutant retained <2, 4.5, 43, 40, and 76% of its aminotransferase activity with Ile, Val, Leu, Met, and Phe, respectively. No difference in growth or acidification rate between LM0230 and the IlvE-deficient strain was observed in milk.


1993 ◽  
Vol 106 (1) ◽  
pp. 31-43 ◽  
Author(s):  
X.R. Wu ◽  
T.T. Sun

Despite the fact that bladder epithelium has many interesting biological features and is a frequent site of carcinoma formation, relatively little is known about its biochemical differentiation. We have shown recently that a 47 kDa glycoprotein, uroplakin III (UPIII), in conjunction with uroplakins I (27 kDa) and II (15 kDa), forms the asymmetric unit membrane (AUM)--a highly specialized biomembrane characteristic of the apical surface of bladder epithelium. Deglycosylation and cDNA sequencing revealed that UPIII contains up to 20 kDa of N-linked sugars attached to a core protein of 28.9 kDa. The presence of an N-terminal signal peptide sequence and a single transmembrane domain located near the C terminus, plus the N-terminal location of all the potential N-glycosylation sites, points to a type I (N-exo/C-cyto) configuration. Thus the mass of the extracellular domain (20 kDa plus up to 20 kDa of sugar) of UPIII greatly exceeds that of its intracellular domain (5 kDa). Such an asymmetrical mass distribution, a feature shared by the other two major uroplakins, provides a molecular explanation as to why the luminal leaflet of AUM is almost twice as thick as the cytoplasmic one. The fact that of the three major proteins of AUM only UPIII has a significant cytoplasmic domain suggests that this molecule may play an important role in AUM-cytoskeleton interaction in terminally differentiated urothelial cells.


1991 ◽  
Vol 279 (1) ◽  
pp. 223-230 ◽  
Author(s):  
P Palomeque-Messia ◽  
S Englebert ◽  
M Leyh-Bouille ◽  
M Nguyen-Distèche ◽  
C Duez ◽  
...  

The low-Mr penicillin-binding protein (PBP)/DD-transpeptidase of Streptomyces K15 is synthesized in the form of a 291-amino acid-residue precursor possessing a cleavable 29-amino acid-residue signal peptide. Sequence-similarity searches and hydrophobic-cluster analysis show that the Streptomyces K15 enzyme, the Escherichia coli PBPs/DD-carboxy-peptidases 5 and 6, the Bacillus subtilis PBP/DD-carboxypeptidase 5 and the spoIIA product (a putative PBP involved in the sporulation of B. subtilis) are structurally related and form a distinct class A of low-Mr PBPs/DD-peptidases. The distribution of the hydrophobic clusters along the amino acid sequences also shows that the Streptomyces K15 PBP, and by extension the other PBPs of class A, have similarity in the polypeptide folding, with the beta-lactamases of class A, with as reference the Streptomyces albus G and Staphylococcus aureus beta-lactamases of known three-dimensional structure. This comparison allows one to predict most of the secondary structures in the PBPs and the amino acid motifs that define the enzyme active sites.


1996 ◽  
Vol 40 (3) ◽  
pp. 616-620 ◽  
Author(s):  
A Bauernfeind ◽  
I Stemplinger ◽  
R Jungwirth ◽  
P Mangold ◽  
S Amann ◽  
...  

Plasmidic extended-spectrum beta-lactamases of Ambler class A are mostly inactive against ceftibuten. Salmonella typhimurium JMC isolated in Argentina harbors a bla gene located on a plasmid (pMVP-5) which confers transferable resistance to oxyiminocephalosporins, aztreonam, and ceftibuten. The beta-lactamase PER-2 (formerly ceftibutenase-1; CTI-1) is highly susceptible to inhibition by clavulanate and is located at a pI of 5.4 after isoelectric focusing. The blaPER-2 gene was cloned and sequenced. The nucleotide sequence of a 2.2-kb insert in vector pBluescript includes an open reading frame of 927 bp. Comparison of the deduced amino acid sequence of PER-2 with those of other beta-lactamases indicates that PER-2 is not closely related to TEM or SHV enzymes (25 to 26% homology). PER-2 is most closely related to PER-1 (86.4% homology), an Ambler class A enzyme first detected in Pseudomonas aeruginosa. An enzyme with an amino acid sequence identical to that of PER-1, meanwhile, was found in various members of the family Enterobacteriaceae isolated from patients in Turkey. Our data indicate that PER-2 and PER-1 represent a new group of Ambler class A extended-spectrum beta-lactamases. PER-2 so far has been detected only in pathogens (S. typhimurium, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis) isolated from patients in South America, while the incidence of PER-1-producing strains so far has been restricted to Turkey, where it occurs both in members of the family Enterobacteriaceae and in P. aeruginosa.


Blood ◽  
1997 ◽  
Vol 90 (7) ◽  
pp. 2634-2643 ◽  
Author(s):  
Vahid Afshar-Kharghan ◽  
José A. López

We investigated the molecular genetic and biosynthetic basis of Bernard-Soulier syndrome in a severely affected white woman. Flow cytometric analysis showed a severe deficiency of glycoprotein (GP) Ib, GP IX, and GP V on the surface of her platelets. Similarly, GP Ibα was undetectable by immunoblot analysis of platelet lysates. Surprisingly, a large quantity of a 70-kD protein (which probably represents a GP Ibα degradation product) was found in the patient's plasma in much greater quantities than in the plasma of an unaffected individual. To analyze the molecular lesion responsible for the disorder, we amplified and sequenced gene segments corresponding to the entire coding regions of the GP Ibα, GP Ibβ, and GP IX genes. The patient was homozygous for a specific GP Ibα allele that contained two tandem VNTR repeats in the region encoding the macroglycopeptide (C variant) and three differences from the published GP Ibα gene sequence. Two mutations were unlikely to be involved in the disorder: the substitution of a single base (T → C) in the second nucleotide of exon 2, which is in the 5′ untranslated region of the GP Ibα transcript, and a silent mutation in the third base of the codon for Arg342 (A → G) that does not change the amino acid sequence. The third mutation was a deletion of the last two bases of the codon for Tyr492 (TAT). This mutation causes a frameshift that alters the GP Ibα amino acid sequence, beginning within its transmembrane region. The mutant polypeptide contains 81 novel amino acids and is 38 amino acids shorter than its wild-type counterpart. The new sequence changes the hydrophobic nature of the transmembrane domain and greatly decreases the net positive charge of what had been the cytoplasmic domain. The deletion mutation was introduced into the GP Ibα cDNA, alone and in combination with the 5′ mutation, and expressed in Chinese hamster ovary (CHO) cells. The deletion alone severely reduced GP Ibα expression on the cell surface. Expression was not decreased further by addition of the 5′ mutation, confirming that the deletion was the cause of the Bernard-Soulier phenotype. Stable cell lines expressing the mutant polypeptide secreted large amounts of the polypeptide into the medium, suggesting that the mutant anchors poorly in the plasma membrane. Nevertheless, a fraction of the mutant was able to associate with GP Ibβ, as demonstrated by their coimmunoprecipitation with a GP Ibβ antibody.


2002 ◽  
Vol 68 (6) ◽  
pp. 2731-2736 ◽  
Author(s):  
Hirokazu Nankai ◽  
Wataru Hashimoto ◽  
Kousaku Murata

ABSTRACT When cells of Bacillus sp. strain GL1 were grown in a medium containing xanthan as a carbon source, α-mannosidase exhibiting activity toward p-nitrophenyl-α-d-mannopyranoside (pNP-α-d-Man) was produced intracellularly. The 350-kDa α-mannosidase purified from a cell extract of the bacterium was a trimer comprising three identical subunits, each with a molecular mass of 110 kDa. The enzyme hydrolyzed pNP-α-d-Man (Km = 0.49 mM) and d-mannosyl-(α-1,3)-d-glucose most efficiently at pH 7.5 to 9.0, indicating that the enzyme catalyzes the last step of the xanthan depolymerization pathway of Bacillus sp. strain GL1. The gene for α-mannosidase cloned most by using N-terminal amino acid sequence information contained an open reading frame (3,144 bp) capable of coding for a polypeptide with a molecular weight of 119,239. The deduced amino acid sequence showed homology with the amino acid sequences of α-mannosidases belonging to glycoside hydrolase family 38.


1999 ◽  
Vol 26 (5) ◽  
pp. 495 ◽  
Author(s):  
Kazumasa Yoshida ◽  
Kiyoshi Tazaki

Three genomic clones (Rplec2, Rplec5 and Rplec6) and a cDNA clone (LECRPA4) that encoded lectin or lectin-related polypeptides were isolated from Robinia pseudoacacia L. A comparison of the nucleotide sequences of Rplec2 and a previously reported cDNA for the subunit indicated that Rplec2 encoded the 29 kDa subunit of the inner-bark lectin RPbAI. Rplec5 encoded a polypeptide whose deduced amino acid sequence was 96.1% identical to that of a subunit of seed lectin. The amino acid sequence deduced from the open reading frame of Rplec6 showed 61.1% identity to that encoded by Rplec5. LECRPA4 was isolated from an inner bark cDNA library and appeared to encode the 26 kDa subunit of inner-bark lectin RPbAII. The expression patterns of the various genes in tissues were examined by the reverse transcriptase-polymerase chain reaction (RT-PCR) with appropriate primers. Rplec2 transcripts were detected in the inner bark and roots. Rplec5 transcripts were detected in the inner bark, seeds and roots. No Rplec6 transcripts were detected in all tissues examined. LECRPA4 transcripts were found in leaves and in the inner bark. The level of expression of Rplec2 in the inner bark appeared to be similar in samples collected in different years and from different trees, whereas levels of expression of Rplec5 and LECRPA4 varied. These results suggest the differential regulation of expression of members of the lectin gene family in tissues of R. pseudoacacia. The nucleotide sequence data reported herein will appear in the DDBJ, EMBL and GenBank Nucleotide Sequence Databases under the accession numbers AB 012632 (Rplec2), AB012633 (Rplec5), AB012634 (Rplec6) and AB012635 (LECRPA4).


1998 ◽  
Vol 42 (11) ◽  
pp. 2906-2913 ◽  
Author(s):  
James M. Battisti ◽  
Laura S. Smitherman ◽  
D. Scott Samuels ◽  
Michael F. Minnick

ABSTRACT This study describes the first isolation and characterization of spontaneous mutants conferring natural resistance to an antibiotic for any Bartonella species. The Bartonella bacilliformis gyrB gene, which encodes the B subunit of DNA gyrase, was cloned and sequenced. The gyrB open reading frame (ORF) is 2,079 bp and encodes a deduced amino acid sequence of 692 residues, corresponding to a predicted protein of ∼77.5 kDa. Sequence alignment indicates that B. bacilliformis GyrB is most similar to the GyrB protein from Bacillus subtilis (40.1% amino acid sequence identity) and that it contains the longest N-terminal tail (52 residues) of any GyrB characterized to date. The cloned B. bacilliformis gyrB was expressed in an Escherichia coli S30 cell extract and was able to functionally complement a temperature-sensitive E. coli Cour gyrB mutant (strain N4177). We isolated and characterized spontaneous mutants of B. bacilliformis resistant to coumermycin A1, an antibiotic that targets GyrB. Sequence analysis of gyrB from 12 Cour mutants ofB. bacilliformis identified single nucleotide transitions at three separate loci in the ORF. The predicted amino acid substitutions resulting from these transitions are Gly to Ser at position 124 (Gly124→Ser), Arg184→Gln, and Thr214→Ala or Thr214→Ile, which are analogous to mutated residues found in previously characterized resistant gyrB genes fromBorrelia burgdorferi, E. coli,Staphylococcus aureus, and Haloferax sp. The Cour mutants are three to five times more resistant to coumermycin A1 than the wild-type parental strain.


1999 ◽  
Vol 65 (12) ◽  
pp. 5546-5553 ◽  
Author(s):  
Kazuhiro Iwashita ◽  
Tatsuya Nagahara ◽  
Hitoshi Kimura ◽  
Makoto Takano ◽  
Hitoshi Shimoi ◽  
...  

ABSTRACT We cloned the genomic DNA and cDNA of bglA, which encodes β-glucosidase in Aspergillus kawachii, based on a partial amino acid sequence of purified cell wall-bound β-glucosidase CB-1. The nucleotide sequence of the cloned bglA gene revealed a 2,933-bp open reading frame with six introns that encodes an 860-amino-acid protein. Based on the deduced amino acid sequence, we concluded that the bglA gene encodes cell wall-bound β-glucosidase CB-1. The amino acid sequence exhibited high levels of homology with the amino acid sequences of fungal β-glucosidases classified in subfamily B. We expressed the bglA cDNA inSaccharomyces cerevisiae and detected the recombinant β-glucosidase in the periplasm fraction of the recombinant yeast.A. kawachii can produce two extracellular β-glucosidases (EX-1 and EX-2) in addition to the cell wall-bound β-glucosidase.A. kawachii in which the bglA gene was disrupted produced none of the three β-glucosidases, as determined by enzyme assays and a Western blot analysis. Thus, we concluded that thebglA gene encodes both extracellular and cell wall-bound β-glucosidases in A. kawachii.


Sign in / Sign up

Export Citation Format

Share Document