Prevalence of Ticks and detection of Rickettsial Agents from blood of Tick-Infested animals in Lower Sindh: A MOLECULAR APPROACH

Ticks are important vectors of human and animal pathogens. They are considered as main vectors for transmission of rickettsial agents affecting animal and human health. The study was designed to investigate district wise pattern and detection of rickettsial agents by using molecular and conventional techniques in blood samples of infected cattles, buffalos, sheeps and goats. A survey study was carried out in lower Sindh (Tharparkar, Badin, Hyderabad, Karachi, Tando Muhammad khan, Thatta and Mirpurkhas). Blood samples were collected randomly from infected Cattles, buffalos, sheeps and goats and transported to the Molecular Parasitology laboratory, Sindh Agriculture University, Tandojam, followed by examinations under stereomicroscope and Polymerase Chain Reaction (PCR). The study showed that overall infection of Rickettsial agents among infected animals was recorded follwoing Microscopy/ Blood smear test in cattles, buffalos, sheeps and goats was 41.79, 49.09, 46 and 41.66% respectively, whereas overall infection through PCR in cattle, buffalo, sheep and goat was 39.55, 43.55, 46 and 55.55% respectively. Whereas animal-wise data through PCR indicates that in case of Goats (55.55%) were more susceptible to rickettsial infection as compared to sheep (46%), buffaloes (43.55%) and cattle (39.55%). The highest rate of rickettsial agents was found in district Tharparkar and lowest rate was found in district Karachi. Microscopy/Blood smear method indicates that Buffaloes were more susceptible for infection. Whereas PCR indicates Goats were more susceptible for infection.

mSphere of Influence: Courage and Resilience in Life and Science

ABSTRACT Anat Florentin works in the field of molecular parasitology, studying the cell biology of malaria parasites. In this mSphere of Influence article, she reflects how the book Brave Genius: a Scientist, a Philosopher, and Their Daring Adventures from the French Resistance to the Nobel Prize by Sean B. Carroll (2013) made a powerful impact on her by telling scientific stories in the context of dramatic life events.

mSphere of Influence: Ushering in the CRISPR Revolution to Toxoplasma Biology

ABSTRACT Alfredo J. Guerra works in the field of molecular parasitology and structural biology. In this mSphere of Influence article, he reflects on how “Efficient Gene Disruption in Diverse Strains of Toxoplasma gondii Using CRISPR/CAS9” by Bang Shen et al. (mBio 5:e01114-14, 2014, https://doi.org/10.1128/mBio.01114-14) and “Efficient Genome Engineering of Toxoplasma gondii using CRISPR/CAS9” by Saima M. Sidik et al. (PLoS One 9:e100450, 2014, https://doi.org/10.1371/journal.pone.0100450) made an impact on him by successfully implementing strategies to genetically manipulate T. gondii using CRISPR/CAS9 gene editing technology.

Mitochondrial genomics of human pathogenic parasiteLeishmania(Viannia)panamensis

BackgroundThe human parasiteLeishmania (V.) panamensisis one of the pathogenic species responsible for cutaneous leishmaniasis in Central and South America. Despite its importance in molecular parasitology, its mitochondrial genome, divided into minicircles and maxicircles, haven’t been described so far.MethodsUsing NGS-based sequencing (454 and ILLUMINA), and combiningde novogenome assembly and mapping strategies, we report the maxicircle kDNA annotated genome ofL. (V.) panamensis, the first reference of this molecule for the subgenusViannia. A comparative genomics approach is performed against otherLeishmaniaandTrypanosomaspecies.ResultsThe results show synteny of mitochondrial genes ofL. (V.) panamensiswith other kinetoplastids. It was also possible to identify nucleotide variants within the coding regions of the maxicircle, shared among some of them and others specific to each strain. Furthermore, we compared the minicircles kDNA sequences of two strains and the results show that the conserved and divergent regions of the minicircles exhibit strain-specific associations.

Cryptosporidium in fish: alternative sequencing approaches and analyses at multiple loci to resolve mixed infections

SUMMARYCurrently, the systematics, biology and epidemiology of piscine Cryptosporidium species are poorly understood. Here, we compared Sanger ‒ and next-generation ‒ sequencing (NGS), of piscine Cryptosporidium, at the 18S rRNA and actin genes. The hosts comprised 11 ornamental fish species, spanning four orders and eight families. The objectives were: to (i) confirm the rich genetic diversity of the parasite and the high frequency of mixed infections; and (ii) explore the potential of NGS in the presence of complex genetic mixtures. By Sanger sequencing, four main genotypes were obtained at the actin locus, while for the 18S locus, seven genotypes were identified. At both loci, NGS revealed frequent mixed infections, consisting of one highly dominant variant plus substantially rarer genotypes. Both sequencing methods detected novel Cryptosporidium genotypes at both loci, including a novel and highly abundant actin genotype that was identified by both Sanger sequencing and NGS. Importantly, this genotype accounted for 68·9% of all NGS reads from all samples (249 585/362 372). The present study confirms that aquarium fish can harbour a large and unexplored Cryptosporidium genetic diversity. Although commonly used in molecular parasitology studies, nested PCR prevents quantitative comparisons and thwarts the advantages of NGS, when this latter approach is used to investigate multiple infections.

David James Kemp 1945–2013

David Kemp's seminal contributions to molecular parasitology of malaria and scabies have placed Australian science at the forefront of research on these important human pathogens. Immunoscreening of expression clones led to the identification of several vaccine candidates against malaria. His contributions to scabies research are pivotal to our understanding of bacteria–parasite–human interactions. Other notable achievements are: the discovery of one of the earliest known multi-gene families; the first cloning of linked variable-region genes in the immunoglobulin heavy-chain locus; the invention of highly cited molecular biology methods, namely Northern blotting and inverted-PCR; and contributions to ‘molecular public health' by his work on various bacterial infections relevant to the health of Indigenous Australians. Kemp's manifest enthusiasm for science was highly infectious. He mentored many high-achieving scientists. In addition to his exemplary career as a scientist, he was a musician at heart and a passionate rock fossicker.

Molecular parasitology in the 21st Century

Protist parasites cause important human and animal diseases, and because of their early divergence from other eukaryotes they possess structural and biochemical characteristics not found in other cells. The completion of the genome projects of most human protist parasites and the development of novel molecular tools for their study guarantee a rapid progress in understanding how they invade, modify and survive within their hosts. The ultimate goal of these studies will be the identification of targets for the design of drugs, diagnostics and vaccines. In addition, the accessibility of some of these parasites to multiple genetic manipulations has converted them into model systems in cell and molecular biology studies that could lead to the understanding of basic biological processes, as well as their evolution and pathogenesis. In the present chapter we discuss the biochemical and molecular peculiarities of these parasites and the molecular tools available for their study.