BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Probing binding affinity of human acetylcholine esterase for stero idal pregnanes as promising inhibitors through molecular modelling investi gation DTSTART;VALUE=DATE-TIME:20230925T080000Z DTEND;VALUE=DATE-TIME:20230925T083000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9270@events.saip.org.za DESCRIPTION:Speakers: Oludare Ogunyemi (University of Ibadan)\nAcetyl Chol ine Esterase (AChE) is one of the most important therapeutic targets for p reventing and treating Alzheimer's disease. Studies have suggested the ACh E inhibitory potential of pregnanes but the mechanism is still elusive. Th e aim of this study was to investigate the binding affinity of AChE enzyme for steroidal pregnanes in silico. Machine learning (ML) models were trai ned based on molecular fingerprints to rapidly screen a library of steroid al pregnanes retrieved from CHEMBL compound database for their half maxima l inhibitory concentration (IC50) and inhibition constant (Ki) against ACh E enzyme. Molecular docking\, Molecular Dynamics (MD) simulation and MMGBS A free energy calculation were employed to further probe the binding affin ity and decipher the binding interactions. Among 42 machine learning model s assessed\, Random Forest Regressor (RF) was a top model with high R-squa red and low RMSE values. From 1\,583 steroidal pregnanes\, RF-based ML mod el screening revealed 843 pregnanes with pIC50 ≥ 5. Among these\, 67 pre gnanes with pKi ≥ 7 were suggested as promising AChE inhibitors. Atomist ic simulations revealed 21-[(3-Hydroxy-2-naphthyl)oxy]pregnane-2-one (P1)\ , 20-[2-(Imidazolidine-2-ylidene)hydrazono]pregnane-3beta-ol (P3) and 17-H ydroxy-3-oxo-19-nor-5beta\,17alpha-pregnane-21-carboxylic acid\, gamma-lac tone (P4) as the Top Docking Pregnanes (TDPs). The top compound (P1) exhib ited the best molecular contacts with the active site\, interacting with t he catalytic active site\, peripheral anionic site (PAS)\, oxyanion hole a nd anionic sub-site through multiple hydrogen bonds and hydrophobic intera ctions. The AChE-TDP complexes exhibited structural stability and conform ational flexibility in a dynamic environment. The RMSF plot revealed the i nteraction potentials of a loop around the PAS with TDPs. Also\, P1 featur ed the strongest MMGBSA binding affinity (ΔG = -19.02±4.37 Kcal/mol) whi ch was contributed mainly by key PAS residues. Furthermore\, the TDPs were predicted to exhibit desirable drug-likeness\, bioavailability and abilit y to cross the blood-brain barrier. Therefore\, the in silico hits are sug gested for experimental biophysical\, biochemical and pre-clinical evaluat ion towards developing potent AChE inhibitors.\n\nhttps://events.saip.org. za/event/238/contributions/9270/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9270/ END:VEVENT BEGIN:VEVENT SUMMARY:Quantum optical mega-networks in biological architectures\, and th e computational capacity of life and the observable universe DTSTART;VALUE=DATE-TIME:20230926T123000Z DTEND;VALUE=DATE-TIME:20230926T130000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9263@events.saip.org.za DESCRIPTION:Speakers: Philip Kurian (Quantum Biology Laboratory\, Howard U niversity)\nIn this talk I will present an overview of our work analyzing mega-networks of tryptophan in biological architectures with numerical sim ulations and steady-state ultraviolet spectroscopy\, providing opportuniti es for control of light-matter interactions in cellular organelles and neu ronal bundles. I will then\, based on these insights and fundamental physi cal considerations\, consider the computational limits of living systems a nd all matter in the observable universe. The implications for development of artificial intelligence(s) will also be discussed.\n\nNetworks of tryp tophan – an aromatic amino acid with strong fluorescent response – are ubiquitous in biological systems\, forming diverse architectures in trans membrane proteins\, cytoskeletal filaments\, sub-neuronal elements\, photo receptor complexes\, virion capsids\, and other cellular structures. We an alyze the cooperative effects induced by ultraviolet (UV) excitation of se veral biologically relevant tryptophan mega-networks\, thus giving insight into novel mechanisms for cellular signalling and control. Our theoretica l analysis in the single-excitation manifold predicts the formation of str ongly superradiant states due to collective interactions among organized a rrangements of up to more than 100\,000 tryptophan UV-excited transition d ipoles in microtubule architectures\, which leads to an enhancement of the fluorescence quantum yield that is confirmed by our experiments. We demon strate the observed consequences of this superradiant behavior in the fluo rescence quantum yield for hierarchically organized tubulin structures\, w hich increases in different geometric regimes at thermal equilibrium befor e saturation – highlighting the effect's persistence in the presence of significant disorder. Our results motivate a revisiting of conventional as sumptions about the computing limits of cytoskeletal and neuronal architec tures\, which are generally considered to signal via Hodgkin-Huxley action potentials (millisecond timescale). It is shown that these biosystems can harness superradiant effects (picosecond timescale) in tryptophan lattice s to process orders of magnitude more information than exascale supercompu ters\, at significantly lower power consumptions\, by operating extremely close to the Landauer bound for logically irreversible operations. The rob ustness of single-photon-excited superradiant states paired with subradian t states (second timescale) in biology thus offers a novel paradigm for un derstanding large collectives of quantum emitters and their quantum inform ation processing limits in warm\, wet\, and wiggly environments.\n\nhttps: //events.saip.org.za/event/238/contributions/9263/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9263/ END:VEVENT BEGIN:VEVENT SUMMARY:Automated Patch Clamp Evaluation of Snake Neurotoxins and Recombin ant Antivenoms DTSTART;VALUE=DATE-TIME:20230926T080000Z DTEND;VALUE=DATE-TIME:20230926T083000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9272@events.saip.org.za DESCRIPTION:Speakers: Kim Boddum (Sophion A/S)\nSnakebite was reinstated a s an official Neglected Tropical Disease (NTD) by the World Health Organiz ation in 2017\, as it causes more than 100\,000 deaths and around 400\,000 amputations every year. Every snake species has a unique venom compositio n and consists of several dozen different toxins. \nThe century-old techni que to generate conventional antivenoms involves immunization horses with snake venoms\, followed by purification of polyclonal antibodies from the horse blood plasma. However\, such antivenoms are associated with several drawbacks related to equine-human immunoreactivity and adverse reactions\, batch-to-batch variation\, and high cost. \nIn the last decade\, advances in antibody engineering have made antibody discovery and development more efficient\, and it is now possible to develop recombinant antivenoms base d on monoclonal antibodies targeting key venom toxin. One of the most medi cally relevant groups of snake toxins are the α-neurotoxins\, which targe t nicotinic acetylcholine receptors (nAChRs). \nFor over two decades\, aut omated patch clamp (APC) systems have been used to advance our understandi ng of ion channel biophysics\, pharmacology\, and their roles in physiolog y and disease. \nHere\, using QPatch II and Qube 384 APC\, we functionally evaluated snake venom α-neurotoxins and toxin-neutralising IgG monoclona l antibodies (mAbs) on the muscle-type α1-nAChR.\nThis study demonstrates the potential of a range of IgGs to neutralize α-neurotoxins from severa l snake species. This is a critically important step towards enabling the design of novel\, broadly-neutralizing recombinant antivenoms against snak ebite envenoming.\nThis work highlights the potential and advantages of us ing high-throughput electrophysiology systems to evaluate the functional a ctivity of protein-based toxins and antibodies.\n\nhttps://events.saip.org .za/event/238/contributions/9272/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9272/ END:VEVENT BEGIN:VEVENT SUMMARY:Recombinant expression and biophysical characterization of NAD-bin ding domain of S. mansoni Glyceraldehyde 3-phosphate dehydrogenase. DTSTART;VALUE=DATE-TIME:20230926T093000Z DTEND;VALUE=DATE-TIME:20230926T100000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9275@events.saip.org.za DESCRIPTION:Speakers: Kagiso Motlhatlhedi (University of Johannesburg)\nSc histosomiasis is a devastating parasitic disease affecting over 200 millio n people globally and has the highest morbidity and mortality in sub-Sahar an Africa. Praziquantel (PZQ) has been the only drug used to treat all sch istosome infections because it is readily available\, cost-effective\, and has minimal side effects. Recent studies have shown that PZQ-resistant st rains are emerging due to drug pressure. Other concerns are that PZQ does not kill the parasite during the reproduction stage\, which is crucial bec ause the disease directly results from eggs’ entrapment in host tissue\, thus increasing the individual’s susceptibility to opportunistic infect ions. Therefore\, it is critical to discover druggable targets and/or vacc ine candidates for schistosomiasis. GAPDH is an enzyme found in the schist osome\, which uses the NAD-binding domain component of its structure to ge nerate energy motility and survival of the worm. Therefore\, GAPDH is an i mportant druggable target in the discovery and development of new anti-sch istosomal agents. Therefore\, the aim of this study is to recombinantly ex press and characterize the NAD-binding domain of GAPDH for future discover y\, design\, and development of new anti-schistosomal drugs. Competent JM1 09 bacteria cells were transformed with the NAD-binding domain of the GAPD H plasmid\, followed by recombinant expression and affinity purification u sing a GST-Agarose column to obtain milligram quantities of the protein. T hereafter\, biophysical characterization using FTIR and Raman spectroscopy was conducted immediately after in silico analysis. Overall\, the S. mans oni NAD binding domain of GAPDH was successfully characterized to provide a structural basis for the development of new anti-schistosomal drugs. Add itionally\, in silico analysis revealed Triosephosphate isomerase and Phos phoglycerate kinase as interacting partners\, which may be critical in the discovery and design of small molecule inhibitors and the subsequent deve lopment of these as new anti-schistosomal compounds.\n\nhttps://events.sai p.org.za/event/238/contributions/9275/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9275/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigation of the Structure\, Stability\, and Solubility of Psi locybin in Water and Pure Organic Solvents: A Molecular Simulation Study DTSTART;VALUE=DATE-TIME:20230926T120000Z DTEND;VALUE=DATE-TIME:20230926T123000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9265@events.saip.org.za DESCRIPTION:Speakers: Lucas Paul (Department of Chemistry\, Dar es Salaam University College of Education\, P.O. Box 2329\, Dar es Salaam\, Tanzania )\nBackground: Psilocybin\, derived from magic mushrooms\, has versatile m edicinal potential\, including neuroprotection and mental health benefits. FDA approval for clinical research suggests promise in treating anxiety\, depression\, and addiction. Nevertheless\, clinical application is hinder ed by solubility issues and neurotoxicity. This study utilizes computation al simulations to explore psilocybin's behavior in organic solvents\, offe ring insights into its stability\, structure\, and solubility challenges\, especially in contrast to its solubility in water.\nMethodology: This stu dy involves investigating psilocybin's characteristics in different solven ts\, including water and 35 common organic solvents. This is done through free energy calculations and detailed structural analysis. The solvation-f ree energy (∆Gsolv) is used to assess the interaction between psilocybin and the solvent\, with a negative value indicating a preference for being in solution. The comparison between psilocybin forms A and B involves ele ctronic structure calculations to establish their ideal gas reference stat es and interconversion energy. The research aims to relate these findings to the relative concentration of psilocybin forms in solution.\nResults: T he study validates the existence of two Psilocybin forms\, A and B\, with form B being thermodynamically more stable through free energy and DFT ana lysis. Hydrogen bonding significantly influences the solvation of Psilocyb in form B\, while aliphatic and non-hydrogen-containing solvents have mini mal coulombic contributions. Alcohols and water exhibit different solvatio n behaviors\, likely due to their unique properties. These results enhance our understanding of Psilocybin's stability and solvation in diverse solv ent environments.\nConclusion: Findings suggest the thermodynamic stabilit y of Psilocybin form B compared to A. Further studies are proposed to inve stigate different forms of solvents like ionic liquids \nKeywords: Psilocy bin\; Solvents\; Solubility\; Stability\; Free energy\n\nhttps://events.sa ip.org.za/event/238/contributions/9265/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9265/ END:VEVENT BEGIN:VEVENT SUMMARY:Shear induced fractionalized dispersion during the Magnetic Drug T argeting in a permeable microvessel DTSTART;VALUE=DATE-TIME:20230928T080000Z DTEND;VALUE=DATE-TIME:20230928T083000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9267@events.saip.org.za DESCRIPTION:Speakers: Sachin Shaw (Botswana International University of Sc ience and Technology)\nTo predict the effective dispersion and saturated c oncentration of the drug carriers\, a Caputo fractional\ntime derivative b ased dispersion model is generated. The impact of the memory effect depend ence\nof solutions on previous instances on the shear augmented dispersion is analyzed during\nthe magnetic drug targeting in the microvessel. The m agnetic nanoparticle are bound with the nonmagnetic\nmaterials/microgels w ith the therapeutic agents to prepare the drug carrier. A magnetic\nfield is created outside the body to control and accelerate the trajectories of the drug carriers. The\nnature of the blood flow into the vessel is consid ered as Casson fluid. The velocity of the drug\ncarrier is solved analytic ally while the fractional-order dispersion equation is solved numerically by\nusing the finite difference method. The influence of fractional-order parameter and model biological\nparameters such as rheological parameter\, permeability parameter related to hydraulic conductivity\,\nmagnetization \, volume fraction of nanoparticles\, tumor-magnet distance\, nanoparticle radius\, drug\nelimination\, and source term on the relative effective di spersion are discussed. The outcomes showed\nthat both rheological paramet ers and volume fractions increase drug carrier particle concentration\,\na nd that saturating occurs at a later time as they increase. The higher mag netization\, the permeability\nparameter related to the hydraulic conducti vity\, and the source term\, the faster drug-coated\ncarriers are transpor ted to the tumor site. In addition\, we indicate that using small particle sizes\,\na high concentration of the drug-coated nanoparticles will be ex pected in the tumor area\, and this\nslows the rate at which it reaches th e saturation point.\n\nhttps://events.saip.org.za/event/238/contributions/ 9267/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9267/ END:VEVENT BEGIN:VEVENT SUMMARY:Travelling waves in inhomogeneous DNA system using Sine-Gordon equ ation DTSTART;VALUE=DATE-TIME:20230928T073000Z DTEND;VALUE=DATE-TIME:20230928T080000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9261@events.saip.org.za DESCRIPTION:Speakers: Mordecai Opoku Ohemeng (KNUST)\nAn impulse function which is as a result of an external factor was considered as a complex dy namic system which has a nonlinear perturbations on the DNA system. This i s used to describe the distortion that occurs within the DNA system. In de scribing the internal dynamics\,mathematical model known as the sine-Gordo n equations was employed. The equation describes angular oscillations of n itrous bases of the chain. The sine-Gordon model was modified to depictthe dynamics of the double helix of a DNA system. The proposed model was base d on the inhomogeneities that exist in the base sequence of the DNA struct ure. Various works that has been done in similar areas were discussed as w ell as the method that was used. The effect of dissipation on the DNA was considered. Computer simulations were performed on the model to see the di stortions that occurs in the DNA system\n\nhttps://events.saip.org.za/even t/238/contributions/9261/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9261/ END:VEVENT BEGIN:VEVENT SUMMARY:The mechanisms of enzymes of the nitrilase superfamily DTSTART;VALUE=DATE-TIME:20230928T070000Z DTEND;VALUE=DATE-TIME:20230928T073000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9273@events.saip.org.za DESCRIPTION:Speakers: Bryan Trevor Sewell (University of Cape Town)\, Dewa ld van Heerden (University of Cape Town)\nOur goal is to determine the mec hanisms of the nitrilase superfamily enzymes. These enzymes have common fe atures such as their fold and conserved residues in their active sites (tw o glutamates\, a lysine and a cysteine) but have a range of different acti vities. The superfamily derives its name from the nitrilases that convert nitriles to the corresponding carboxylic acids and ammonia\, but most of t he enzymes in the superfamily are amidases that convert amides to the corr esponding carboxylic acid and ammonia. The reaction proceeds via the forma tion of a thioester intermediate. In our recent work [1] we identified the components of the active site that position the amide substrate for the a ttack by the cysteine on the carbonyl carbon of the amide. Our approach\, which has led to several key insights\, involves a combination of structur e analysis\, site directed mutagenesis\, identification of intermediates b y mass spectroscopy and quantum mechanical modelling [2]. An example of su ch an insight\, shown in Fig. 1\, locates the water molecule that is respo nsible for the hydrolysis of the thioester intermediate such that its lone pair overlaps with the LUMO of the carbonyl carbon.\nMany amidase homo-ol igomers\, ranging from 2-8 monomers in different instances\, have been cry stallized\, leading to extensive structural knowledge. The nitrilases\, on the other hand\, form spiral homo-oligomeric structures and\, to date\, n one have crystallized in their complete\, active form. The spiral structur es are\, however\, amenable to structure determination by cryoEM [5]. In t he case of Nit4 from Arabidopsis thaliana side chains in two adjacent mono mers contribute to the active site pocket\, playing an important role in s ubstrate specificity. This enables enzymes to be tailored to a wide variet y of substrates.\n\nhttps://events.saip.org.za/event/238/contributions/927 3/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9273/ END:VEVENT BEGIN:VEVENT SUMMARY:Discovery and Characterization of Cancer Mutations on DNA Transact ion Enzymes DTSTART;VALUE=DATE-TIME:20230926T113000Z DTEND;VALUE=DATE-TIME:20230926T120000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9274@events.saip.org.za DESCRIPTION:Speakers: G. Andres Cisneros (University of Texas at Dallas)\n We have developed a comprehensive approach to find and characterize the im pact of cancer mutants on target proteins\, and have applied it to DNA mod ification enzymes. This approach is an extension of conventional genome wi de–association studies (GWAS). Our approach employs a new method for dis covery and statistical validation of single nucleotide polymorphisms (SNPs ) on specific genes called HyDn–SNP–S\, followed by atomistic simulati ons via molecular dynamics (MD) and/or quantum mechanics/molecular mechani cs (QM/MM) techniques. We will present the details of our mutant discovery and characterization approach\, as well as examples of characterization o f cancer mutations on DNA modification enzymes. Our simulations provide in sights at the atomic level about how these mutations affect protein struct ure and/or function. Furthermore\, experimental results validating our pre dictions will be presented.\n\nhttps://events.saip.org.za/event/238/contri butions/9274/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9274/ END:VEVENT BEGIN:VEVENT SUMMARY:Overexpression\, purification\, and characterization of the Hsp70. 14 protein towards the discovery and development of new anti-cancer compou nds DTSTART;VALUE=DATE-TIME:20230926T090000Z DTEND;VALUE=DATE-TIME:20230926T093000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9262@events.saip.org.za DESCRIPTION:Speakers: Tshepang Ndaba (University of Johannesburg)\nCancer remains one of the leading causes of death\, with over 2 million cases wor ldwide. New therapeutic approaches are therefore under constant developmen t\, aimed at eliminating various pathways/mechanisms utilized by cancerous cells. Previous studies have investigated the molecular interaction betwe en the Heat shock protein 70.14 (Hsp70.14) and the RING finger domain of R etinoblastoma binding protein 6 (RBBP6) to determine how this interaction contributes to the progression of cancer. Disruption of this interaction t hrough the discovery and development of protein-protein interaction (PPI) modulators serves as one of the potential therapeutic approaches that can be used to reduce the development of cancer. Hence this present study aime d at the recombinant expression\, purification\, and characterization of t he Hsp70.14 protein\, one of the interacting partners of RBBP6. Hsp70.14 w as expressed in competent Top10 E. coli cells\, purified using affinity ch romatography\, and thereafter characterized using FTIR and Raman spectrome try. Additionally\, in silico methods were used to computationally charact erize and predict the structure of the protein. The results show that the protein predominantly contains hydrophilic residues\, and its structure is made up of two alpha helices and three anti-parallel beta strands\, which was successfully validated using a Ramachandran plot and a Qmean swiss mo del. FTIR results revealed a high number of carbonyl and hydroxyl groups p resent in the protein whilst Raman data displayed symmetric C-C stretching and CH2 twisting vibrations in the fingerprint region of the protein resp ectively. These characterizations provided the basis for the structural de termination of the protein and the subsequent identification of the residu es important in the interaction with this RING domain partner for the disc overy and design of new anti-cancer biopharmaceuticals.\n\nhttps://events. saip.org.za/event/238/contributions/9262/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9262/ END:VEVENT BEGIN:VEVENT SUMMARY:Using quantitative fluorescence correlation spectroscopy to study aggregation of the main photosynthetic antenna of plants DTSTART;VALUE=DATE-TIME:20230926T073000Z DTEND;VALUE=DATE-TIME:20230926T080000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9266@events.saip.org.za DESCRIPTION:Speakers: Francois Conradie ()\nOxygenic organisms are capable of tuning their photosynthetic capacity on many different timescales to a dapt to their environment. As such\, they switch on photoprotective mechan isms to harvest solar energy with robust adaptability. Studying these mech anisms at the molecular level gives insight into how solar energy harvesti ng can sustain life on earth and which design principles can be used to im prove man-made solar energy devices.\nPhotosynthetic antennae are pigment- protein complexes that absorb sunlight and transfer the energy towards rea ction centres in photosystems. These complexes exhibit fast heat-dissipati ve processes that protect them from photo-induced chemical bleaching. In h igher plants\, aggregation of these complexes amplifies heat dissipation\, a process triggered by a lowering of the pH on the inner side of thylakoi d membranes. \n\nThis presentation will describe a home-built fluorescence correlation spectroscopy setup and its use to study freely diffusing ligh t-harvesting complexes of plants *in-vitro* at varying detergent concentra tion levels and pH levels. We will focus on the dynamics of the main plant light-harvesting complex\, LHCII. Varying sizes of LHCII aggregates were investigated and their fluorescence lifetimes were obtained\, allowing a d irect comparison of aggregate sizes with quenching rates. In addition\, we will show how triplet state lifetimes can be resolved through this techni que on freely diffusing and immobilised single complexes.\n\nhttps://event s.saip.org.za/event/238/contributions/9266/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9266/ END:VEVENT BEGIN:VEVENT SUMMARY:Real-time feedback-driven single-particle tracking spectroscopy of LHCII DTSTART;VALUE=DATE-TIME:20230926T070000Z DTEND;VALUE=DATE-TIME:20230926T073000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9264@events.saip.org.za DESCRIPTION:Speakers: Bertus van Heerden (University of Pretoria)\nSingle- molecule spectroscopy (SMS) has proven to be a powerful technique for inve stigating structure-function relationships in light-harvesting systems. In particular\, SMS has unraveled dynamics in light-harvesting complexes tha t are hidden in ensemble measurements. However\, the environment used in S MS experiments is a poor representation of the natural cellular environmen t\, and therefore the results of these studies may be of limited physiolog ical relevance. One limitation of conventional SMS experiments is the need to immobilize the complexes via surface attachment or to trap the complex es using\, e.g.\, an anti-Brownian electrokinetic (ABEL) trap. This limita tion is overcome by real-time feedback-driven single-particle tracking (RT -FD-SPT)\, a non-invasive technique that allows SMS measurements to be per formed on single\, freely diffusing particles for extended durations and w ith excellent spatiotemporal resolution. We studied different RT-FD-SPT m ethods using statistical analysis and simulations before using RT-FD-SPT t o experimentally measure fluorescence lifetimes and emission spectra of si ngle diffusing plant LHCII complexes. This paves the way for studies of th e effect of surface immobilization as well as for studying single LHCII co mplexes in close-to-natural environments.\n\nhttps://events.saip.org.za/ev ent/238/contributions/9264/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9264/ END:VEVENT BEGIN:VEVENT SUMMARY:DEVELOPMENT OF BIOCOMPATIBLE DRUG CARRIERS FOR IMPROVED DRUG LOADI NG AND RELEASE PROFILES DTSTART;VALUE=DATE-TIME:20230925T083000Z DTEND;VALUE=DATE-TIME:20230925T090000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9271@events.saip.org.za DESCRIPTION:Speakers: Gerald Gration (University of Dar Es Salaam)\nExtens ive research has focused on developing effective and biocompatible\ndrugs and drug-delivery systems. Capsaicin\, a natural compound found in\nhot pe ppers\, has potential therapeutic properties\, such as pain relief and ant iinflammatory effects. However\, its clinical application is limited by lo w cellular\nabsorption\, chemical instability\, poor aqueous solubility\, and some side effects\,\nsuch as skin irritation and burning sensation. Le cithin\, a phospholipid with\nbiocompatibility and liposome-forming abilit ies\, can be used in drug delivery\nsystems. Both capsaicin and lecithin e xhibit hydrophilic and hydrophobic characteristics\, allowing them to self -assemble in aqueous solutions for drug loading\nand release.\nMolecular d ocking and molecular dynamics\, two crucial computational techniques in th e fields of computational chemistry and structural biology\, are\ninstrume ntal for scrutinizing molecular interactions\, especially in the context\n of drug discovery and protein-ligand interactions. In this study\, we empl oy\nthese methodologies to investigate the self-assembly behaviour of caps aicin and\nlecithin in an aqueous environment\, revealing strong self-asse mbly into welldefined\, arbitrarily shaped aggregates. The hydrophilic-hyd rophobic nature of\nthe materials enables improved drug loading and contro lled release. Furthermore\, the carrier enhances the physicochemical prope rties of capsaicin by forming stable complexes through nonbonded interacti ons. These findings inform\nthe development of new drug delivery systems t hat utilize the self-assembly\nproperties of amphiphilic molecules to impr ove the delivery and effectiveness of\nhydrophobic drugs.\nThe distance be tween the hydrophobic groups in capsaicin and lecithin appears to be small er compared to the hydrophilic groups. The spacing ranges\nfrom 0.33 to 0. 62 nm and 1.28 to 1.48 nm\, respectively\, this variation is because\nof a n increased concentration of lecithin monomers\, which ranges from 1-8. In creasing the concentration of lecithin has an impact on the rotation angle of\ncapsaicin at the centre\, reducing it from 123° to less than 60° an d increasing\nthe availability of water surrounding it. Additionally\, an increase in lecithin\nconcentration affects the arrangement of atoms attac hed to it. For example\,\nthe distance between the hydrogen of the hydroxy l group and the oxygen of\nthe methoxy group increases from 0.25nm to 0.44 nm\, allowing more water to\ninteract with capsaicin\, thereby enhancing i ts ability to dissolve in water.\nThese observations suggest that hydropho bic groups play a crucial role in facilitating the rapid entrapment of cap saicin via hydrophobic forces. As the concentration of lecithin increases\ , the complex becomes more stable\, strengthening\nthe hydrophobic forces that hold capsaicin tightly and reducing its flexibility\,\nwhich is cruci al for effective loading and release.\n\nhttps://events.saip.org.za/event/ 238/contributions/9271/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9271/ END:VEVENT BEGIN:VEVENT SUMMARY:Molecular Dynamics Simulation on the Structural Stability and Solv ation of Irinotecan in Water and Organic Solvents DTSTART;VALUE=DATE-TIME:20230925T073000Z DTEND;VALUE=DATE-TIME:20230925T080000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9269@events.saip.org.za DESCRIPTION:Speakers: Martin MEDARD (MSc student/Researcher)\nIrinotecan\n Solubility\nSolvation Free Energy\n\nhttps://events.saip.org.za/event/238/ contributions/9269/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9269/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigation of the Impact of the Ionic Liquid on the Solubility of Acyclovir Derivative through Computational Analysis DTSTART;VALUE=DATE-TIME:20230925T070000Z DTEND;VALUE=DATE-TIME:20230925T073000Z DTSTAMP;VALUE=DATE-TIME:20260909T133908Z UID:indico-contribution-238-9268@events.saip.org.za DESCRIPTION:Speakers: MICHAEL MTANGA (Student)\nAcyclovir derivative is on e of the most nucleoside analogs used as an antiviral drug for treatment o f chickenpox\, simplex virus infection and shingles. Acyclovir derivative like other analogs facing with poor solubility in water and organic solven t hindering its bioavailability and membrane permeation. To deal with this problem\, Ionic liquid emerged to be potential candidate with the ability to improve the solubility of these drugs. To understand this\, solvation mechanism was identified computationally. The findings shows that\, Ionic liquid has high ability to improve the solubility of these drugs. From the results various factors that contribute to increase in the solubility of the drug was discussed including the contribution of van der waals and ele ctrostatic interaction.\n\nhttps://events.saip.org.za/event/238/contributi ons/9268/ LOCATION: URL:https://events.saip.org.za/event/238/contributions/9268/ END:VEVENT END:VCALENDAR