English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  The simian malaria parasite  Plasmodium knowlesi  has been reported to cause significant numbers of human infection in South East Asia. Its merozoite surface protein-3 (MSP3) is a protein that belongs to a multi-gene family of proteins first found in  Plasmodium falciparum . Several studies have evaluated the potential of  P. falciparum  MSP3 as a potential vaccine candidate. However, to date no detailed studies have been carried out on  P. knowlesi  MSP3 gene ( pkmsp3 ). The present study investigates the genetic diversity, and haplotypes groups of  pkmsp3  in  P. knowlesi  clinical samples from Peninsular Malaysia.    Methods  Blood samples were collected from  P. knowlesi  malaria patients within a period of 4 years (2008–2012). The  pkmsp3  gene of the isolates was amplified  via  PCR, and subsequently cloned and sequenced. The full length  pkmsp3  sequence was divided into Domain A and Domain B. Natural selection, genetic diversity, and haplotypes of  pkmsp3  were analysed using MEGA6 and DnaSP ver. 5.10.00 programmes.    Results  From 23 samples, 48  pkmsp3  sequences were successfully obtained. At the nucleotide level, 101 synonymous and 238 non-synonymous mutations were observed. Tests of neutrality were not significant for the full length, Domain A or Domain B sequences. However, the dN/dS ratio of Domain B indicates purifying selection for this domain. Analysis of the deduced amino acid sequences revealed 42 different haplotypes. Neighbour Joining phylogenetic tree and haplotype network analyses revealed that the haplotypes clustered into two distinct groups.    Conclusions  A moderate level of genetic diversity was observed in the  pkmsp3  and only the C-terminal region (Domain B) appeared to be under purifying selection. The separation of the  pkmsp3  into two haplotype groups provides further evidence of the existence of two distinct  P. knowlesi  types or lineages. Future studies should investigate the diversity of  pkmsp3  among  P. knowlesi  isolates in North Borneo, where large numbers of human knowlesi malaria infection still occur.    Electronic supplementary material  The online version of this article (doi:10.1186/s13071-016-1935-1) contains supplementary material, which is available to authorized users.

Genetic clustering and polymorphism of the merozoite surface protein-3 of Plasmodium knowlesi clinical isolates from Peninsular Malaysia