Immunology
Hong Chen; Jiawu Wan; Meihua Wei; Ping Liu; Lingbao Kong; Xiu Xin
Volume 15, Issue 2 , February 2024, , Pages 65-73
Abstract
The non-structural protein (nsp) 8 of the porcine epidemic diarrhea virus (PEDV) is highly stable across different PEDV strains and plays an important role in PEDV virulence. In current study, nsp8 prokaryotic expression vectors were constructed based on parental vectors pMAL-c2x-maltose binding protein ...
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The non-structural protein (nsp) 8 of the porcine epidemic diarrhea virus (PEDV) is highly stable across different PEDV strains and plays an important role in PEDV virulence. In current study, nsp8 prokaryotic expression vectors were constructed based on parental vectors pMAL-c2x-maltose binding protein (MBP) and pET-28a (+). Subsequently, the optimization of expression conditions in Escherichia coli, including induced temperature, time and isopropyl β-D-thiogalactopyranoside concentration were performed to obtain a stable expression of MBP-nsp8 and nsp8. The nsp8 fused with MBP increased the water solubility of the expressed products. Target proteins were further purified from E. coli culture and their immunogenicities were evaluated in vivo by mice. The antibody titers of serum from nsp8 immunized mice were up to 1:7,750,000 when measured by indirect enzyme-linked immunosorbent assay; meanwhile, the mice immunized with MBP-nsp8 gave an antibody titer reaching 1:1,000,000. In all, the expression and purification system of PEDV nsp8 and MBP-nsp8 were successfully established in this work and a strong immune response was elicited in mice by both purified nsp8 and MBP-nsp8, providing a basis for the study of the structure and function of PEDV nsp8.
Abd Allah Ahmed Mokhbatly; Nahawand Elsheikh; Emad Wadeed Ghazy; Adel Mohamed Elgamal; Yamen Mohammed Hegazy; Doaa Hosny Assar
Volume 13, Issue 2 , June 2022, , Pages 155-162
Abstract
Lamb enteritis constitutes an economic burden on sheep production worldwide. We aimed to estimate the prevalence of Shiga toxin-producing Escherichia coli (STEC) and Salmonellae among diarrheic lambs at Kafrelsheikh Governorate, Egypt and to detect the associated clinical, hematologic, biochemical, and ...
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Lamb enteritis constitutes an economic burden on sheep production worldwide. We aimed to estimate the prevalence of Shiga toxin-producing Escherichia coli (STEC) and Salmonellae among diarrheic lambs at Kafrelsheikh Governorate, Egypt and to detect the associated clinical, hematologic, biochemical, and antioxidant parameters. Fifty diarrheic and twenty apparently healthy control lambs were examined clinically, and hematologically. Diarrheic lambs had a significant elevated body temperature, respiratory and pulse rate, most of hemogram para-meters, total proteins and albumin, oxidative stress markers malonaldiahyde and nitric oxide levels, liver enzymes, urea and creatinine than control group. On the other hand, these diarrheic lambs had significant reduction in total leukocyte count and lymphocytes, antioxidant biomarkers super oxide dismutase activities and reduced glutathione than control lambs. E. coli and Salmonella spp. were isolated from 32.00% and 16.00% of diseased lambs, respectively. Serotyping and biochemical tests of examined samples identified 16 E. coli isolates belonged to 10 different serotypes; O6, O8, O26:H11, O75, O84:H21, O103:H2, O114:H4, O121:H7, O128:H2 and O163:H2. All isolates are STEC as they harbor either Shiga-toxin 1 or Shiga-toxin 2 genes or both. One isolate carries intimin gene (eaeA) and classified as EHEC; O26:H11. The obtained nine isolates of Salmonella carry enterotoxin (Stn) genes, eight of them carry hyper-invasive locus (hilA) gene, all isolates belonged to six serotypes; S. Enteritidis, S. Heidelberg, S. Tsevie, S. Typhimurium, S. Essen, and S. Infantis. Lamb diarrhea was prevalent in the studied area and might constitute a veterinary and public health threat. Alteration in hemato-biochemical para-meters and oxidative–anti-oxidant balance could help adopt appropriate treatment regimens.
Mohsen Kalantari; Hassan Sharifiyazdi; Keramat Asasi; Bahman Abdi-Hachesoo
Volume 12, Issue 1 , March 2021, , Pages 101-107
Abstract
The objective was to investigate the multidrug resistance and presence of class 1 and 2 integrons in 300 Escherichia coli isolates obtained from 20 broiler farms during three rearing periods (one-day-old chicks, thirty-day-old chickens, and one day before slaughter) in Fars, South Iran. Results ...
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The objective was to investigate the multidrug resistance and presence of class 1 and 2 integrons in 300 Escherichia coli isolates obtained from 20 broiler farms during three rearing periods (one-day-old chicks, thirty-day-old chickens, and one day before slaughter) in Fars, South Iran. Results showed that 81.00%, 82.00%, and 85.00% of isolates were multidrug-resistant on the first day, thirty-day-old chickens, and one day before slaughter, respectively. Multidrug-resistant E. coli isolates were further examined for the presence of class 1 and 2 integrons using PCR assay. The existence of class 1 integron-integrase gene (intI1) was confirmed in 68.40%, 72.70%, and 60.90% of multidrug-resistant isolates from stage 1, stage 2, and stage 3 of the rearing period, respectively. The frequency of class 2 integron-integrase gene (intI2) during the first to the third stage of sampling was 2.60%, 25.50%, and 30.40%. Also, sequence analysis of the cassette arrays within class 1 integron revealed the presence of the genes associated with resistance for trimethoprim (dfrA), streptomycin (aadA), erythromycin (ereA), and orfF genes. The results revealed that percentages of antimicrobial resistance in E. coli isolates were significantly higher in the middle and end stages of the rearing period. In conclusion, widespread dissemination of class 1 integrons in all three stages and rising trends of class 2 integrons existence in E. coli isolates during the rearing period of broiler chickens could exacerbate the spread of resistance factors among bacteria in the poultry industry. Future research is needed to clarify its implication for human health.
Microbiology
Soheila Najafi; Morad Rahimi; Zahra Nikousefat
Volume 10, Issue 1 , March 2019, , Pages 43-49
Abstract
Pathogenic Escherichia coli strains cause a wide range of extra intestinal infections including urinary tract infection in humans and colibacillosis in poultry. They are classified into uropathogenic E. coli (UPEC) and avian pathogenic E. coli (APEC) with genetic similarities and variations. Their ...
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Pathogenic Escherichia coli strains cause a wide range of extra intestinal infections including urinary tract infection in humans and colibacillosis in poultry. They are classified into uropathogenic E. coli (UPEC) and avian pathogenic E. coli (APEC) with genetic similarities and variations. Their pathogenicity is related to the virulence-encoding genes like sfa, papG II, ompT, iutA, and iss with zoonotic potentials. One hundred isolated E. coli from patients with urinary tract infection and 100 E. coli from chickens with colibacillosis were evaluated for the presence of the most common virulence-encoding genes including sfa, papG II, ompT, iutA, and iss by multiplex polymerase chain reaction. While the frequency of sfa, papG II, ompT, iutA and iss encoding genes in APEC isolates were respectively 0.00%, 67.00%, 63.00%, 89.00% and 89.00%, the frequency of these encoding genes in UPEC isolates were 18.00%, 40.00%, 40.00%, 74.00% and 48.00%, respectively. Except for sfa, the frequencies of other encoding genes in APEC were more than those in UPEC isolates. The iutA as the most common UPEC encoding gene and iss as the most common APEC encoding gene were the most prevalent virulence factors in the examined E. coli isolates. Finding out the distribution of virulence-associated genes could be helpful to identify similarities and differences between APEC and UPEC isolates in order to provide more substantial evidence of their common virulence traits and potential zoonotic threats.
Immunology
Fereshteh Yazdani; Mehran Bakhshesh; Majid Esmaelizad; Zohre Azita Sadigh
Volume 8, Issue 3 , September 2017, , Pages 209-213
Abstract
Bovine ephemeral fever is an acute and arthropod-borne viral disease of cattle and water buffalo which occurs seasonally in most of the world tropical and subtropical regions. The epizootic feature of the disease has been reported in Iran with serious economic consequences. The surface glycoprotein G ...
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Bovine ephemeral fever is an acute and arthropod-borne viral disease of cattle and water buffalo which occurs seasonally in most of the world tropical and subtropical regions. The epizootic feature of the disease has been reported in Iran with serious economic consequences. The surface glycoprotein G of bovine ephemeral fever virus (BEFV) is composed of 4 antigenic sites (G1-G4) and plays the main role for eliciting neutralizing antibodies and protective immunity. The G1 – epitope is a linear antigenic site and conserved among BEFV strains. In order to develop an ELISA test based on G1-epitope as coating antigen, this study was carried out to express the recombinant G1-epitope of BEFV in prokaryotic system. Using PCR and specific primers, a length of 88 amino acid of the G glycoprotein of BEFV including G1- epitope was amplified and cloned into the expression vector pGEX-4T-1, with the GST moiety. The recombinant plasmid (pGEX-4T-1-G1) was then transformed into Escherichia coli BL21 and expression of fusion protein was induced by 0.10 mM IPTG. The maximum expression of the fusion protein was obtained at 16 hr post induction as verified by SDS-PAGE electrophoresis, and it was also confirmed that this protein bearing G1- epitope is sufficiently biologically active to bind to anti-BEFV serum in western blot experiment.
