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Biology subjects

Abid, M.

Publications and source records attributed to Abid, M..

3 recordsLinked to original sources

Chaperonin activity of Plasmodium prefoldin complex is essential to guard proteotoxic stress response and presents a new target for drug discovery

The intraerythrocytic growth of malaria parasite is challenged by the presence of proteotoxic stress and intrinsically unstructured proteins in the cytoplasm due to formation of toxic heme during haemoglobin digestion. To overcome the unavoidable stress and maintain the cellular protein homeostasis, parasite encodes for a number of chaperones and co-chaperones. Here, we functionally characterize the Plasmodium falciparum prefoldins (PfPFD1-6), a hexameric co-chaperone complex, for their role in protein homeostasis. We demonstrate that PfPFD1-6 localise to cytosol of the parasite and the subunits perform an orchestrated interaction (-PFD3-PFD2-PFD1-PFD5-PFD6-PFD4-) to form an active jelly-fish like complex. Biperiden, an N-propylpiperidine analogue identified by chemotype search from FDA, strongly binds and restricts the formation of prefoldin complex and inhibited its interaction with the substrates, PfMSP-1 and -tubulin-I. Biperiden treatment potently inhibited the in vitro (IC50: 1M) and in vivo growth of malaria parasite. Thus, this study provides novel virtues towards understanding the role of PfPFDs in regulating protein homeostasis and opens new avenues for drug discovery against malaria.

molecular biology↗

Biological evaluation of novel side chain containing CQTrICh-analogs as antimalarials and their development as PfCDPK1 kinase inhibitors

To combat the emergence of drug resistance against the existing antimalarials, novel side chain containing 7-chloroquinoline-indole-chalcones tethered with a triazole (CQTrICh-analogs 7 (a-s) and 9) were designed and synthesized by reacting substituted 1-phenyl-3-(1-(prop-2-yn-1- yl)-1H-indol-3-yl) prop-2-en-1-one and 1-(prop-2-yn-1-yl)-1H-indole-3-carbaldehyde with 4- azido-7-chloroquinoline, respectively via a click reaction. The selected CQTrICh-analogs: 7l and 7r inhibited chloroquine-sensitive (3D7) and resistant (RKL-9) strains of Plasmodium falciparum, with IC50 values of 2.4 {micro}M & 1.8 {micro}M (7l), and 3.5 {micro}M & 2.7 {micro}M (7r), respectively, and showed insignificant hemolysis and cytotoxicity in mammalian cells. Intra-erythrocytic progression studies revealed that the active hybrids: 7l and 7r are effective against the mature stages of the parasite. Given the importance of Calcium-Dependent Protein Kinase 1 (PfCDPK1) in the parasite biology, notably during late schizogony and subsequent invasion of merozoites into host RBCs, we identified this protein as a possible molecular target of these active hybrids. In silico interaction analysis indicated that 7l and 7r stably interact with the catalytically active ATP-binding pocket of PfCDPK1, by the formation of energetically favorable H-bonds. Furthermore, in vitro Microscale Thermophoresis and kinase assays with recombinant PfCDPK1 demonstrated that the active hybrids interact with and inhibit the kinase activity, thus presumably responsible for the parasite growth inhibition. Interestingly, 7l and 7r showed no inhibitory effect on the human kinases, indicating that they are selective for the parasite kinase. Conceivably, we report the antiplasmodial potential of novel kinase targeting bio-conjugates, a step towards developing pan-kinase inhibitors, which is a prerequisite for cross-stage anti-malarial protection. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=115 SRC="FIGDIR/small/498981v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@113574borg.highwire.dtl.DTLVardef@c81a33org.highwire.dtl.DTLVardef@1301d22org.highwire.dtl.DTLVardef@1c8cac5_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

COVID-19 Knowledge, Attitudes, and Practices of United Arab Emirates Medical and Health Sciences Students: A Cross Sectional Study

COVID-19 pandemic is the largest unprecedented viral pandemic of the 21st century. We aimed to study the COVID-19 knowledge, attitudes, and practices (KAP) among medical and health sciences students in the United Arab Emirates (UAE). We performed a cross-sectional study between 2nd June and 19th August 2020. The survey was developed using online Survey Monkey. The link was distributed via UAE University to all students and via WhatsApp(C) groups. The self-administered questionnaire was conducted in English and comprised of two parts: socio-demographic characteristics and KAP towards COVID-19. A total of 712 responses to the questionnaire were collected. 90% (n=695) were under-graduate, while 10% (n=81) were post-graduate students. Majority (87%, n=647) stated that they obtained COVID-19 information from multiple reliable sources. They were highly knowledgeable about COVID-19 pandemic but 76% (n=539) did not recognize its routes of transmission. 63% (n=431) were worried of getting COVID-19, while 92% (n=633)) were worried that a family member could get infected with the virus. 97% (n=655) took precautions when accepting home deliveries, 94% (n=637) had been washing their hands more frequently, and 95% (n=643) had been wearing face masks. In conclusion, participants showed high levels of knowledge and awareness about COVID-19. They were worried about getting infected themselves or their family members, and had good practices against COVID-19.

scientific communication and education↗