Genetic diversity of secreted protein with an altered thrombospondin repeat (SPATR) of Plasmodium knowlesi clinical isolates from Malaysia
Document Type
Article
Publication Date
12-1-2022
Abstract
The Plasmodium knowlesi secreted protein with an altered thrombospondin repeat (PkSPATR) is an important protein that helps in the parasite's invasion into the host cell. This protein has been regarded as one of the potential vaccine candidates against P. knowlesi infection. This study investigates the genetic diversity and natural selection of PkSPATR gene of P. knowlesi clinical isolates from Malaysia. PCR amplification of the full length PkSPATR gene was performed on 60 blood samples of infected P. knowlesi patients from Peninsular Malaysia and Malaysian Borneo. The amplified PCR products were cloned and sequenced. Sequence analysis of PkSPATR from Malaysia showed higher nucleotide diversity (CDS p: 0.01462) than previously reported Plasmodium vivax PvSPATR (p = 0.0003). PkSPATR from Peninsular Malaysia was observed to have slightly higher diversity (CDS p: 0.01307) than those from Malaysian Borneo (CDS p: 0.01212). Natural selection analysis on PkSPATR indicated significant purifying selection. Multiple amino acid sequence alignment revealed 69 polymorphic sites. The phylogenetic tree and haplotype network did not show any distinct clustering of PkSPATR. The low genetic diversity level, natural selection and absence of clustering implied functional constrains of the PkSPATR protein.
Keywords
Plasmodium knowlesi, SPATR, genetic diversity, haplotype analysis
Divisions
Parasit
Funders
Ministry of Education Malaysia Long Term Research Grant Scheme [LRGS/1/2018/UM/01/1/1]
Publication Title
TROPICAL BIOMEDICINE
Volume
39
Issue
4
Publisher
MALAYSIAN SOC PARASITOLOGY TROPICAL MEDICINE
Publisher Location
21-5-2, BLOCK, E, DIAMOND SQUARE, JALAN 3-50, OFF JALAN GOMBAK, KUALA LUMPUR, MALAYSIA