1
|
Citarová A, Mojžišová J, Petroušková P, Pelegrinová A, Kostičák M, Korytár L, Prokeš M, Vojtek B, Ondrejková A, Drážovská M. Investigation of canine parvovirus occurrence in cats with clinical signs of feline panleukopenia in Slovakia - pilot study. J Vet Res 2024; 68:199-205. [PMID: 38947159 PMCID: PMC11210359 DOI: 10.2478/jvetres-2024-0021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 03/28/2024] [Indexed: 07/02/2024] Open
Abstract
Introduction Feline panleukopenia is a contagious viral disease caused by the feline panleukopenia virus (FPV). A closely related pathogen is canine parvovirus (CPV), and amino acid substitutions in this virus allow it to acquire a feline host range. In feline hosts, the disease induced by CPV manifests with similar symptoms to those caused by FPV or milder ones, leading to its underdiagnosis. The aim of this study was to determine the presence of CPV type 2 (CPV-2) in cats with clinical symptoms of panleukopenia and to assess the use of commercial CPV antigen tests for the clinical diagnosis of FPV. Material and Methods Samples from 59 cats from central Slovakia were included in the study. Rectal swabs were collected and clinically tested for parvovirus infection using a commercial antigen test. Antigen-positive samples were confirmed by PCR targeting the viral VP2 gene. The sequences of the PCR products were established with the Sanger method. Results Of 59 samples, 23 were revealed to be positive for parvovirus infection by both antigen and PCR test (38.9%). Analysis with the National Center for Biotechnology Information BLASTn application showed 99.78-100% pairwise identity with FPV. The mortality rate of parvovirus-infected cats included in this study was 8.69% (2/23). Conclusion Although feline disease with CPV-2 was not confirmed, the CPV antigen test was able to detect FPV infection.
Collapse
Affiliation(s)
- Alexandra Citarová
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Jana Mojžišová
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Patrícia Petroušková
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Andrea Pelegrinová
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Maroš Kostičák
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - L’uboš Korytár
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Marián Prokeš
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Boris Vojtek
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Anna Ondrejková
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| | - Monika Drážovská
- Department of Epizootiology, Parasitology and Protection of One Health, University of Veterinary Medicine and Pharmacy in Košice, 041 81Košice, Slovak Republic
| |
Collapse
|
2
|
Bakde RA, Rathish RL, John L, Deepa PM, Vijayakumar K. A novel loop-mediated isothermal amplification (LAMP) assay to diagnose feline panleukopenia. J S Afr Vet Assoc 2024; 95:49-54. [PMID: 38533815 DOI: 10.36303/jsava.597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Abstract
Protoparvovirus carnivoran1, known commonly as feline panleukopenia virus (FPV) is a highly contagious and environmentally stable parvovirus of domestic as well as wild felids. A rapid and robust diagnostic tool will aid in implementing prompt treatment and control measures. A loop-mediated isothermal amplification (LAMP) as a point-of-care diagnostic tool for diagnosing feline panleukopenia was standardised using faecal samples of cats. The assay will reduce the cost and time required to diagnose feline panleukopenia. A set of two outer primers (F3 and B3) and two inner primers (FIP and BIP) were designed to target the viral polypeptide (VP2) gene of FPV. Optimisation of the LAMP reaction was done at 60 °C for one hour after an initial denaturation at 95 °C for five minutes. Visualisation of the result based on the addition of SYBR Green 1 dye offered an easy and reliable diagnosis. The detection limit of the standardised LAMP assay was as low as 1.25 ng/μl of the target DNA. Species specificity of the LAMP primers revealed no amplification of the non-target DNA of any other species except that of the canine parvovirus DNA template. DNA extracted from 100 PCR-positive and 20 PCR-negative faecal samples were subjected to the standardised assay and compared with PCR. Analysis of the results revealed that the LAMP assay was 100% sensitive and 90% specific compared to PCR. The LAMP assay could be a reliable tool for the point-of-care diagnosis of feline panleukopenia in limited resource settings.
Collapse
Affiliation(s)
- R A Bakde
- Department of Veterinary Epidemiology and Preventive Medicine, College of Veterinary and Animal Sciences, Kerala Veterinary and Animal Sciences University, India
| | - R L Rathish
- Department of Veterinary Epidemiology and Preventive Medicine, College of Veterinary and Animal Sciences, Kerala Veterinary and Animal Sciences University, India
| | - L John
- Department of Veterinary Biochemistry, College of Veterinary and Animal Sciences, Kerala Veterinary and Animal Sciences University, India
| | - P M Deepa
- Department of Veterinary Epidemiology and Preventive Medicine, College of Veterinary and Animal Sciences, Kerala Veterinary and Animal Sciences University, India
| | - K Vijayakumar
- College of Veterinary and Animal Sciences, Kerala Veterinary and Animal Sciences University, India
| |
Collapse
|
3
|
Hasırcıoglu S, Aslım HP, Kale M, Bulut O, Koçlu O, Orta YS. Molecular characterization of carnivore protoparvovirus strains circulating in cats in Turkey. PESQUISA VETERINÁRIA BRASILEIRA 2023. [DOI: 10.1590/1678-5150-pvb-7178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
ABSTRACT: Cats are susceptible to feline panleukopenia virus (FPV) and canine parvovirus type 2 (CPV-2). Therefore, coinfection and superinfection with multiple parvovirus strains may occur, resulting in high heterogeneity and recombination. Considering the importance of cats as a potential source of genetic diversity for parvoviruses, we investigated the frequency of parvovirus infection in cats using their blood and fecal samples and performed molecular characterization of parvovirus strains circulating in cat populations. Accordingly, the fecal and blood samples of 60 cats with gastroenteritis symptoms were collected from Turkey’s Burdur, Isparta, and Izmit provinces. Of these 15 fecal samples tested as parvovirus-positive by PCR, 14 were confirmed to have been infected with true FPV strains by sequencing analysis. Through the phylogeny analysis, those were located in the FPV cluster, closely related to CPV-2, and one was discriminated in the CPV-2b cluster. Additionally, sequence analysis of the VP2 gene of CPV and FPV revealed that the FPV strains detected in Turkey and the vaccine strains were highly related to each other, with a nucleotide identity of 97.7- 100%. Furthermore, 13 variable positions were detected in VP2 of the field and reference FPV strains. Three synonymous mutations were determined in the VP2 gene. Some amino acid mutations in the VP2 protein-affected sites were considered responsible for the virus’s biological and antigenic properties. The partial sequence analysis of the VP2 gene revealed that four FPV strains detected in Turkey have a single nucleotide change from T to G at the amino acid position 384 between the nucleotides 3939-3941, which was reported for the first time. Therefore, these four isolates formed a different branch in the phylogenetic tree. The results suggest that both FPV and CPV-2b strains are circulating in domestic cats in Turkey and cats should be considered as potential sources of new parvovirus variants for cats, dogs and other animals.
Collapse
|
4
|
Zou J, Yu J, Mu Y, Xie X, Wang R, Wu H, Liu X, Xu F, Wang J, Wang Y. Development of a TaqMan-based multiplex real-time PCR for simultaneous detection of four feline diarrhea-associated viruses. Front Vet Sci 2022; 9:1005759. [PMID: 36406081 PMCID: PMC9669448 DOI: 10.3389/fvets.2022.1005759] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 10/17/2022] [Indexed: 09/29/2023] Open
Abstract
Since their recent discovery, the prevalence of novel feline enteric viruses, including feline bocavirus 1 (FBoV-1), feline astrovirus (FeAstV), and feline kobuvirus (FeKoV), has been reported in China. Co-infections of these viruses with feline parvovirus (FPV) are common causes of diarrhea in cats. Viral co-infections are difficult to identify because of their non-specific clinical signs. To detect and identify these viruses, a quick and specific pathogen-testing approach is required. Here, we establish a real-time PCR (qPCR) based on multiple TaqMan probes for the simultaneous detection of FBoV-1, FeAstV, FeKoV, and FPV. Specific primers and TaqMan fluorescent probes were designed to ensure specificity. The results showed that the detection limit of single qPCR was up to 10 copies, and the detection limit of multiplex qPCR was up to 100 copies, with correlation coefficients >0.995 in all cases. Clinical sample detection revealed a 25.19% (34/135) total rate of co-infection among the viruses and a 1.48% (2/135) quadruple infection rate. Thus, this multiplex qPCR approach can serve as a quick, sensitive, and specific diagnostic tool for FBoV-1, FeAstV, FeKoV, and FPV identification, and it may be utilized for routine surveillance of these emerging and reemerging feline enteric viruses.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Yong Wang
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| |
Collapse
|
5
|
Chen X, Wang J, Zhou Y, Yue H, Zhou N, Tang C. Circulation of heterogeneous Carnivore protoparvovirus 1 in diarrheal cats and prevalence of an A91S feline panleukopenia virus variant in China. Transbound Emerg Dis 2022; 69:e2913-e2925. [PMID: 35737580 DOI: 10.1111/tbed.14641] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 06/13/2022] [Accepted: 06/19/2022] [Indexed: 11/28/2022]
Abstract
Cats are susceptible to panleukopenia virus (FPV) and canine parvovirus type 2 (CPV-2) infection. FPV has been recognized as relatively conservative in genetic evolution compared to CPV-2, but information regarding FPV variations in cats are still limited. The aim of this study was to investigate the molecular prevalence of FPV and CPV-2 variants among cats in China. From April 2019 to December 2021, 193 diarrheal fecal samples of cats were collected from Southwest China and 127 (65.80 %) samples tested positive to Carnivore protoparvovirus 1. FPV, CPV-2 and some their genomic variants were identified from positive samples, indicating a heterogeneous Carnivore protoparvovirus 1 circulation in the cat population in China. Among FPV strains, an A91S FPV mutant reached the detection rate of 39.37 %, which showed that this FPV genomic variant has been prevalent in the tested cats. Moreover, 7 strains of A91S FPV variants were isolated and purified successfully using F81 cells, and the genomes were sequenced. Phylogenetic trees based on the nearly complete genomic sequences, VP2 and NS1 nucleotide sequences showed that the A91S FPV variants were located in the FPV clade, but all clustered into a separate branch. Structural prediction showed that A91S mutation in VP2 protein extended the random coil of aa residues from 92-95 to 91-95. Moreover, the analysis of all complete VP2 sequences of FPV and CPV-2 available in the GenBank database revealed that the A91S FPV variant has been prevalent in China since 2017 and has reported in four other countries in cats. Thus, our study revealed that heterogeneous Carnivore protoparvovirus 1 are circulating in the cat population in China, and first reported the prevalence and genomic characteristics of the A91S FPV variant, which contributed to a better understanding of the molecular prevalence and genetic evolution of FPV in cats. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Xi Chen
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Jiali Wang
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Yuxing Zhou
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Hua Yue
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Ning Zhou
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| | - Cheng Tang
- College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China
| |
Collapse
|
6
|
Karanam B, Srinivas MV, Vasu J, Xavier AP, Karuppiah R, Shanmugam VP, Mukhopadhyay HK. Phylodynamic and genetic diversity of parvoviruses of cats in southern India. Virusdisease 2022; 33:108-113. [PMID: 35493752 PMCID: PMC9005569 DOI: 10.1007/s13337-022-00760-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 02/04/2022] [Indexed: 11/30/2022] Open
Abstract
Feline panleukopenia virus (FPV) and Canine parvovirus (CPV) infections are highly contagious diseases causing severe gastroenteritis with high fatality rates in cats. Realising the importance of cats as a potential source of genetic diversity for parvoviruses, the present study trace the evolutionary history and dynamics of parvovirus variants by characterizing the full-length viral polypeptide 2 (VP2) gene of parvovirus from domestic cats and cats from rescue shelters in Southern India. The study confirmed the presence of both CPV and FPV infections among the cat population. The full-length VP2 gene analysis of parvoviruses from cats; five had amino acid variations characteristic of FPV and one sequence was New CPV-2a/FPV. Three new mutations (hitherto not reported) were identified at 303rd, 441st and 554th amino acid positions. One potential recombination event was identified in VP2 sequence from a cat (New CPV-2a / FPV recombinant). The molecular analysis confirmed that cat populations are susceptible to CPV variants and FPV, thereby promoting superinfection and co-infection with multiple parvoviruses and potentially facilitating transmission, recombination and high genetic heterogeneity. Supplementary Information The online version contains supplementary material available at 10.1007/s13337-022-00760-4.
Collapse
Affiliation(s)
- Bhaswanth Karanam
- Department of Veterinary Microbiology, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, 605 009 India
| | - Mouttou Vivek Srinivas
- Department of Veterinary Microbiology, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, 605 009 India
| | - Jayalakshmi Vasu
- Department of Veterinary Microbiology, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, 605 009 India
| | - Antony Prabhakar Xavier
- Department of Veterinary Microbiology, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, 605 009 India
| | - Rajkumar Karuppiah
- Department of Veterinary Medicine, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, India
| | - Venkatesa Permal Shanmugam
- Department of Veterinary Biochemistry, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, India
| | - Hirak Kumar Mukhopadhyay
- Department of Veterinary Microbiology, Rajiv Gandhi Institute of Veterinary Education and Research, Puducherry, 605 009 India
| |
Collapse
|
7
|
Emerging Parvoviruses in Domestic Cats. Viruses 2021; 13:v13061077. [PMID: 34200079 PMCID: PMC8229815 DOI: 10.3390/v13061077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 11/16/2022] Open
Abstract
Parvovirus infections in cats have been well known for around 100 years. Recently, the use of molecular assays and metagenomic approaches for virus discovery and characterization has led to the detection of novel parvovirus lineages and/or species infecting the feline host. However, the involvement of emerging parvoviruses in the onset of gastroenteritis or other feline diseases is still uncertain.
Collapse
|
8
|
Giraldo-Ramirez S, Rendon-Marin S, Ruiz-Saenz J. Phylogenetic, Evolutionary and Structural Analysis of Canine Parvovirus (CPV-2) Antigenic Variants Circulating in Colombia. Viruses 2020; 12:v12050500. [PMID: 32366040 PMCID: PMC7290427 DOI: 10.3390/v12050500] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 02/07/2023] Open
Abstract
Canine parvovirus (CPV-2) is the causative agent of haemorrhagic gastroenteritis in canids. Three antigenic variants—CPV-2a, CPV-2b and CPV-2c—have been described, which are determined by variations at residue 426 of the VP2 capsid protein. In Colombia, the CPV-2a and CPV-2b antigenic variants have previously been reported through partial VP2 sequencing. Mutations at residues Asn428Asp and Ala514Ser of variant CPV-2a were detected, implying the appearance of a possible new CPV-2a variant in Colombia. The purpose of the present study was to characterise the full VP2 capsid protein in samples from Antioquia, Colombia. We conducted a cross-sectional study with 56 stool samples from dogs showing clinical symptoms of parvoviral disease. Following DNA extraction from the samples, VP2 amplification was performed using PCR and positive samples were sequenced. Sequence and phylogenetic analyses were performed by comparison with the VP2 gene sequences of the different CPV-2 worldwide. VP2 was amplified in 51.8% of the analysed samples. Sequencing and sequence alignment showed that 93.1% of the amplified samples belonged to the new CPV-2a antigenic variant previously. Analysing the amino acid sequences revealed that all CPV-2a contain Ala297Asn mutations, which are related to the South America I clade, and the Ala514Ser mutation, which allows characterization as a new CPV-2a sub-variant. The Colombian CPV-2b variant presented Phe267Tyr, Tyr324Ile and Thr440Ala, which are related to the Asia-I clade variants. The CPV-2c was not detected in the samples. In conclusion, two antigenic CPV-2 variants of two geographically distant origins are circulating in Colombia. It is crucial to continue characterising CPV-2 to elucidate the molecular dynamics of the virus and to detect new CPV-2 variants that could be becoming highly prevalent in the region.
Collapse
|
9
|
Abstract
Feline panleukopenia (FPL) is caused by a Carnivore protoparvovirus infection. Feline parvovirus (FPV) causes most cases. When Canine parvovirus 2 (CPV-2) first emerged, it could not replicate in cats. All current CPV variants (CPV-2a-c) can infect cats to cause subclinical disease or FPL. Feline panleukopenia has re-emerged in Australia in shelter cats associated with failure to vaccinate. Parvoviruses can remain latent in mononuclear cells post-infection. Molecular methods such as polymerase chain reaction are used to determine the infecting strain. Current perspectives on causes, epidemiology, diagnosis, treatment, prognostic indicators, and management of outbreaks in shelters are reviewed.
Collapse
Affiliation(s)
- Vanessa R Barrs
- Sydney School of Veterinary Science, Faculty of Science, and Marie Bashir Institute of Infectious Diseases & Biosecurity, University of Sydney, New South Wales 2006, Australia.
| |
Collapse
|
10
|
Li X, Wu H, Wang L, Spibey N, Liu C, Ding H, Liu W, Liu Y, Tian K. Genetic characterization of parvoviruses in domestic cats in Henan province, China. Transbound Emerg Dis 2018; 65:1429-1435. [PMID: 30188020 DOI: 10.1111/tbed.13014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 08/28/2018] [Accepted: 08/30/2018] [Indexed: 11/29/2022]
Abstract
Feline panleukopenia virus (FPV) and canine parvovirus (CPV) infections are highly contagious and cause serious enteric diseases, with high fatality rates of cats and dogs. Given the importance of cats as a potential source of genetic diversity for parvoviruses, parvovirus strains detected in cats with gastroenteritis signs were analysed, and molecular characterisation, sequence analysis and phylogeny were evaluated on the VP2 gene. The results showed that FPV, new CPV-2a, and CPV-2 are co-circulating in the cat population in Henan province of China. Moreover, CPV-2 strains (F2016020, and F2016021) with Ser297Ala substitution in VP2 protein was for the first time detected in cats with clinical gastroenteritis. This study provided new important findings about the evolutionary of parvovirus infection in domestic cats.
Collapse
Affiliation(s)
- Xiangdong Li
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Hongchao Wu
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Lingxiao Wang
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Norman Spibey
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Caihong Liu
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Hangtian Ding
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Wujie Liu
- National Research Center for Veterinary Medicine, Luoyang, China
| | - Yuxiu Liu
- National Research Center for Veterinary Medicine, Luoyang, China.,College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Kegong Tian
- National Research Center for Veterinary Medicine, Luoyang, China.,College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| |
Collapse
|
11
|
Molecular characterization of canine parvovirus in Vientiane, Laos. Arch Virol 2017; 162:1355-1361. [PMID: 28124140 DOI: 10.1007/s00705-016-3212-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 12/16/2016] [Indexed: 12/18/2022]
Abstract
The global emergence of canine parvovirus type 2c (CPV-2c) has been well documented. In the present study, 139 rectal swab samples collected from diarrheic dogs living in Vientiane, Laos, in 2016 were tested for the presence of the canine parvovirus (CPV) VP2 gene by PCR. The results showed that 82.73% (115/139) of dogs were CPV positive by PCR. The partial VP2 gene was sequenced in 94 of the positive samples; 91 samples belonged to CPV-2c (426Glu) subtype, while 3 samples belonged to the CPV-2a (426Asn) subtype. Notably, phylogenetic analysis of amino acid sequences revealed a close relationship between Laotian isolates and novel Chinese CPV-2c isolates. In Laotian CPV isolates, aligned protein sequences indicated a high rate of residue substitutions at positions 305, 324, 345, 370, 375, and 426 in the GH loop. The mutation at residue 370 (Q370R), a single mutation, was characterized as a unique mutant residue specific to the Laotian CPV-2c variant.
Collapse
|