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"MRSA (Methicillin-Resistant Staphylococcus aureus) adalah jenis spesies bakteri S. aureus yang resisten terhadap antibiotik metisilin dan antibiotik beta laktam lainnya. Infeksi MRSA menjadi salah satu penyebab utama infeksi nosokomial dan sering kali terkait dengan tingkat kesakitan, kematian, durasi rawat inap yang panjang, dan beban biaya yang substansial. Resistensi MRSA dikaitkan dengan produksi jenis enzim PBP2 baru yaitu PBP2a yang memiliki afinitas yang rendah terhadap β-laktam. Penelitian ini bertujuan untuk mendapatkan parameter optimum untuk penapisan virtual dengan metode penambatan molekular senyawa inhibitor PBP2a menggunakan AutoDock Vina serta mendapatkan 10 kandidat senyawa yang berpotensi sebagai inhibitor PBP2a dari hasil penambatan menggunakan parameter optimum. Pada penelitian ini dilakukan penapisan virtual kandidat inhibitor penicillin-binding protein 2a (PBP2a dari pangkalan data HerbalDB menggunakan penambatan molekuler. Proses optimasi dan validasi menghasilkan parameter terbaik adalah ukuran gridbox 20,625Å x 20,625Å x 20,625Å dengan exhaustiveness 16 menggunakan Autodock Vina yang menghasilkan nilai EF1% 0 dan AUC 0,6428. Berdasarkan hasil penapisan diperoleh 10 peringkat senyawa terbaik menggunakan Autodock Vina yaitu, 7-(2''-p-coumaroylglucoside), 2’’-o-galloylisovitexin, Prunin 6’’-p-coumarate, Withanolide D, Epigallocatechin , 6-methoxypulcherrimin, Beta-cyclanoline, Artonin S, Quercetin 3-rhamnoside-7-glucoside, dan Epicatechin 3, 5-di-o-gallate.

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MRSA (Methicillin-Resistant Staphylococcus aureus) is a type of S. aureus bacterial species that is resistant to the antibiotic methicillin and other beta lactam antibiotics. MRSA infection is one of the main causes of nosocomial infections and is often associated with high levels of morbidity, mortality, long duration of hospitalization, and substantial cost burden. MRSA resistance is associated with the production of a new type of PBP2 enzyme, namely PBP2a, which has a low affinity for β-lactams. This study aims to obtain optimum parameters for virtual screening using the molecular docking method for PBP2a inhibitor compounds using AutoDock Vina and to obtain 10 candidate compounds that have the potential to act as PBP2a inhibitors from the docking results using optimum parameters. In this study, virtual screening of penicillin-binding protein 2a (PBP2a) inhibitor candidates was carried out from the HerbalDB database using molecular docking. The optimization and validation process resulted in the best parameters being a gridbox size of 20.625Å x 20.625Å x 20.625Å with exhaustiveness of 16 using Autodock Vina which resulted an EF1% value 0 and AUC 0.6428. Based on the screening results, the 10 best compound rankings were obtained using Autodock Vina, namely, 7-(2''-p-coumaroylglucoside), 2’’-o-galloylisovitexin, Prunin 6’’-p-coumarate, Withanolide D, Epigallocatechin , 6-methoxypulcherrimin, Beta-cyclanoline, Artonin S, Quercetin 3-rhamnoside-7-glucoside, and Epicatechin 3, 5-di-o-gallate."

"Methicillin-resistant Staphylococcus aureus (MRSA) telah menyebar luas dan menjadi penyebab utama infeksi, baik di masyarakat maupun rumah sakit. MRSA tidak hanya berdampak bagi kesehatan, tetapi juga menimbulkan implikasi ekonomi serius dengan perkiraan kontribusi yang signifikan terhadap kematian dalam dekade mendatang. Penicillin-binding Protein 2a (PBP2a) merupakan protein tambahan pada membran bakteri Staphylococcus aureus yang bertanggung jawab atas resistensinya terhadap antibiotik β-laktam, termasuk metisilin. Dalam penelitian ini, senyawa yang diketahui memiliki aktivitas sebagai inhibitor PBP2a digunakan sebagai training set dan active set. Training set digunakan untuk membuat model farmakofor menggunakan metode shared dan merged pada perangkat lunak LigandScout. Model dari metode shared menghasilkan skor tertinggi sebesar 0,8525 dengan fitur dua daerah hidrofobik (H) dan satu akseptor ikatan hidrogen (HBA). Sementara itu, Model dari metode merged menghasilkan skor tertinggi sebesar 0,8053 dengan fitur empat akseptor ikatan hidrogen (HBA). Setelah dilakukan optimasi dan validasi menggunakan active set dan decoy set, model farmakofor terbaik berasal dari model yang dibangun menggunakan metode shared dengan penurunan weight sebesar 0,1 pada fitur farmakofor H1. Parameter analisis yang diperoleh adalah AUC100%; EF1%; EF5%; sensitivitas; dan spesifisitas yang berturut-turut senilai 0,67; 3,9; 3,1; 0,65; dan 0,60. Model farmakofor terbaik digunakan untuk melakukan penapisan virtual pada pangkalan data HerbalDB. Pemeringkatan senyawa kandidat dilakukan berdasarkan pharmacophore-fit score tertinggi. Senyawa kandidat yang termasuk dalam peringkat sepuluh tertinggi adalah Trigonelloside C, (S)-6-Gingerol, Epicatechin-(4β→6)-epicatechin-(4β→8)-catechin, Mesuol, Scutellarein 7-glucosyl-(1→4)-rhamnoside, trans-p-Ferulyl alcohol 4-O-[6-(2-methyl-3-hydroxypropionyl)] glucopyranoside, 3’-Deoxymaysin, 15-HETE, Proanthocyanidin A1, dan Anhydrosafflor yellow B.

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Methicillin-resistant Staphylococcus aureus (MRSA) has spread widely and become a major cause of infections in both the community and hospitals. MRSA not only impacts health but also has serious economic implications, with a significant contribution to mortality expected in the coming decade. Penicillin-binding Protein 2a (PBP2a) is an additional protein on the membrane of the Staphylococcus aureus responsible for its resistance to β-lactam antibiotics, including methicillin. In this study, compounds known to have activity as PBP2a inhibitors were used as the training set and active set. The training set was used to create pharmacophore models using the shared and merged methods in the LigandScout software. The model from the shared method achieved the highest score of 0.8525 with features of two hydrophobic regions (H) and one hydrogen bond acceptor (HBA). Meanwhile, the model from the merged method achieved the highest score of 0.8053 with features of four hydrogen bond acceptors (HBA). After validation and optimization using the active set and decoy set, the best pharmacophore model was obtained from the shared method with a weight reduction of 0.1 on the H1 pharmacophore feature. The analysis parameters obtained were AUC100%; EF1%; EF5%; sensitivity; and specificity which score were 0,67; 3,9; 3,1; 0,65; dan 0,60 respectively. The best pharmacophore model was used for virtual screening on the HerbalDB database. Candidate compounds were ranked based on the highest pharmacophore-fit score, with the top ten candidate compounds being Trigonelloside C, (S)-6-Gingerol, Epicatechin-(4β→6)-epicatechin-(4β→8)-catechin, Mesuol, Scutellarein 7-glucosyl-(1→4)-rhamnoside, trans-p-Ferulyl alcohol 4-O-[6-(2-methyl-3-hydroxypropionyl)] glucopyranoside, 3’-Deoxymaysin, 15-HETE, Proanthocyanidin A1, dan Anhydrosafflor yellow B."

"This dissertation comprehensively demonstrates how two universally conserved guanosine triphosphatases in the signal recognition particle and its membrane receptor maintain the efficiency and fidelity of the co-translational protein targeting process essential to all cells. A series of quantitative experiments reveal that the highly ordered and coordinated conformational states of the machinery are the key to their regulatory function. This dissertation also offers a mechanistic view of another fascinating system in which multistate protein machinery closely control critical biological processes."

"Penelitian ini bertujuan untuk mengetahui laju pertumbuhan maksimum mikroalga yang dikultivasi dalam medium NPK Urea dan kandungan protein pada sampel kering mikroalga dengan metode uji absorbansi spektrofotometri uv-visible. Jenis mikroalga yang digunakan dalam penelitian ini adalah Chlorella vulgaris dan Spirulina plantesis. Laju pertumbuhan maksimum diperoleh dari tiga metode hitung yaitu haemositometer, absorbansi dan kapasitansi. Laju pertumbuhan maksimum Chlorella vulgaris diperoleh pada hari ketujuh masa kultivasi dengan jumlah 4.752.000 sel/ml dan Spirulina plantesis pada hari keenam dengan jumlah 64.000 sel/ml. Pengujian kandungan protein menggunakan alkaline copper reagen (ACR) yang memanfaatkan reaksi antara larutan tembaga (Cu2+), NaOH dan sampel. Perubahan warna sampel menjadi ungu menandakan adanya reaksi antara Cu2+ dengan ikatan peptida atau protein. Besarnya konsentrasi protein dapat diketahui dengan melihat nilai serapan pada panjang gelombang 520 nm. Kandungan protein yang dihasilkan dari berat kering sampel (w/w) dalam penelitian ini sebesar 14,78% untuk Chlorella vulgaris dan 16,06% untuk Spirulina plantesis. Jenis asam amino yang teridentifikasi berdasarkan perbandingan grafik BSA dengan sampel adalah tyrosin, phenylalanine dan tryptophan.

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This study has purpose to determine the maximum growth rate of microalgae cultivation in the NPK Urea medium and protein content on a dry microalgae sample with UV-visible absorbance spectrophotometry assay method. Type of microalgae used in this study was Chlorella vulgaris and Spirulina plantesis. The maximum growth rate is calculated using three methods: haemocytometer, absorbance and capacitance. Chlorella vulgaris maximum growth rate obtained on the seventh day of cultivation period with the number 4.752.000 cells/ml and Spirulina plantesis on the sixth day with the number 64.000 cells/ml. The protein content was tested using alkaline copper reagent (ACR) which utilizes the reaction between copper (Cu2+), NaOH and samples. The color change of samples turn to purple indicates there are reaction between Cu2+ and peptide bonds or protein. The amount of protein concentration can be determined by looking the absorption value at 520 nm wavelength. The result of protein content of the dry sample weight (w/w) in this study amounted to 14.78% for Chlorella vulgaris and 16.06% for Spirulina plantesis. Types of amino acid were identified by comparison with a standart BSA is tyrosine, phenylalanine and tryptophan."

"Poly(ADP-ribose) Polymerase-1 (PARP-1) merupakan enzim yang berperan pada proses perbaikan DNA Single Strand Break (SSB) yang mengkatalisis proses Poly(ADP-ribosyl)ation atau PARylation. Kerusakan DNA yang terdapat pada sel kanker kolorektal memicu enzim PARP-1 untuk memperbaiki kerusakan tersebut dan menjaga kelangsungan hidup sel kanker. Inhibisi PARP-1 dilakukan untuk mencegah perbaikan DNA yang terjadi pada sel kanker kolorektal. Penelitian ini dilakukan secara studi in silico dengan metode penapisan virtual terhadap senyawa bahan alam yang terdapat pada pangkalan data HerbalDB untuk mendapatkan senyawa yang berpotensi sebagai inhibitor PARP-1. Penelitian ini menggunakan makromolekul dengan PDB ID 6NRI dari laman RCSB PDB. Parameter terbaik yang didapatkan dari proses optimasi dan validasi yang digunakan dalam proses penapisan virtual adalah menggunakan program AutoDock Vina dalam PyRx dengan ukuran grid box 18,75 Å x 18,75 Å x 18,75 Å, nilai exhaustiveness 8, dan num modes 9. Proses penapisan virtual menghasilkan 10 senyawa dengan afinitas penambatan terbaik, yaitu Cassiamin C (-13,9 kkal/mol), Epigallocatechin 3,3’,-di-o-gallate (-11,8 kkal/mol), Chitranone (-11,7 kkal/mol), Cassameridine (-11,6 kkal/mol), Palmarumycin CP1 (-11,4 kkal/mol), Yuehchukene (-11,3 kkal/mol), Gallocatechin-(4alpha-8)-epigallocatechin-3-o-gallate (-11,1 kkal/mol), Roxburghine B (-11,1 kkal/mol), Proanthocyanidin A1 (-11 kkal/mol), dan Withanolide (-11 kkal/mol). Berdasarkan afinititas penambatannya, kesepuluh senyawa tersebut memiliki potensi sebagai kandidat inhibitor PARP-1 dan dapat digunakan untuk penelitian lebih lanjut.

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Poly(ADP-ribose) Polymerase-1 (PARP-1) is an enzyme that plays a role in the DNA Single Strand Break (SSB) repair process that catalyzes the process of Poly(ADP-ribosyl)ation or PARylation. DNA damage in colorectal cancer cells triggers the PARP-1 enzyme to repair the damage and keep cancer cells alive and replicate. PARP-1 inhibition was performed to prevent DNA repair that occurs in colorectal cancer cells. This research is an in silico study with a virtual screening method for natural compounds contained in the HerbalDB database to obtain compounds that have potential as PARP-1 inhibitors. This study uses a macromolecule with PDB ID 6NRI from the RCSB PDB page. The best parameter obtained from the optimization and validation process used in the virtual filtering process is using the AutoDock Vina program in PyRx with a grid box size of 18.75 x 18.75 x 18.75 , exhaustiveness value of 8, and num mode 9. Virtual screening process shows 10 compounds with the best binding affinity, namely Cassiamin C (-13.9 kcal/mol), Epigallocatechin 3,3’,-di-o-gallate (-11.8 kcal/mol), Chitranone (-11.7 kcal/mol ), Cassameridine (-11.6 kcal/mol), Palmarumycin CP1 (-11.4 kcal/mol), Yuehchukene (-11.3 kcal/mol), Gallocatechin-(4alpha-8)-epigallocatechin-3 -o- gallate (-11.1 kcal/mol), Roxburghine B (-11.1 kcal/mol), Proanthocyanidin A1 (-11 kcal/mol), and Withanolide (-11 kcal/mol). Based on their binding affinity, the ten compounds have potential as PARP-1 inhibitor candidates and can be used for further research.

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"In this volume, Peter Tompa and Monika Fuxreiter have assembled a series of papers that address the issue of fuzziness in molecular interactions. These papers provide a broad overview of the phenomenon of fuzziness and provide compelling examples of the central role played by fuzzy interactions in regulation of cellular signaling processes and in viral infectivity. These contributions summarize the current state of knowledge in this new field and will undoubtedly stimulate future research that will further advance our understanding of fuzziness and its role in biomolecular interactions."

"Penggunaan antibodi monoklonal, seperti alirocumab dan evolocumab sebagai inhibitor PCSK9 telah disetujui oleh U.S. FDA dan European Medicines Agency karena mampu menurunkan kadar LDL. Tetapi, kedua obat ini hanya dapat diadministrasikan secara parenteral sehingga para peneliti masih mencari alternatif lain untuk mengatasi keterbatasan tersebut. Pada penelitian ini, senyawa dari golongan tetrahidroisoquinolin, fenilpiperazin, fenilalanin, dan benzofuran digunakan sebagai training set untuk mendapatkan model farmakofor yang berpotensi sebagai inhibitor PCSK9. Tahapan seperti pembuatan model farmakofor, validasi, optimasi, serta penapisan virtual dilakukan melalui LigandScout. Model farmakofor yang terbangkitkan memiliki skor 0,7031 dengan empat fitur farmakofor, yaitu satu AR, satu H, satu HBA, dan satu HBD. Model farmakofor kemudian dioptimasi menggunakan active set dari ligan terpilih dan decoy set dari DUD-E. Optimasi dengan penambahan feature weight sebesar 0,1 terhadap keempat fitur tersebut memberikan hasil validasi terbaik yang ditunjukkan dengan nilai AUC100%, EF1%, EF5%, sensitivitas, dan spesifisitas berturut-turut sebesar 0,93; 34,0%; 6,0%; 1,00; dan 0,79. Hasil penapisan virtual menggunakan model farmakofor tersebut kemudian dievaluasi berdasarkan kaidah Lipinski’s Rule of Five dengan KNIME. Sebelas senyawa bahan alam dari HerbalDB yang berpotensi untuk dikembangkan menjadi terapi anti-PCSK9 dalam bentuk sediaan peroral, antara lain morindone, gentisin, mesuaxanthone A, beta-phenethylamine, brazilin, pterofuran, n-cis- feruloyltyramine, bethanidine, 6-methoxykaempferol, gartanin, dan alizarin.

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The use of alirocumab and evolocumab as PCSK9 inhibitors has been approved by U.S. FDA and European Medicines Agency because of their ability to reduce LDL levels. However, these monoclonal antibodies must be administered parenterally, so researchers are devising alternative strategies to overcome its limitation. In this study, tetrahydroisoquinoline, phenylpiperazine, phenylalanine, and benzofuran compound groups were used as training sets to obtain a pharmacophore model. The process of making a pharmacophore model, validation, optimization, and virtual screening were done using LigandScout. The generated pharmacophore model scored 0.7031 with four pharmacophore features, namely one AR, one H, one HBA, and one HBD. The model was then optimized using the active and decoy set from DUD-E. Optimization by increasing the feature weight by 0,1 to the four features gave the best validation result as indicated by the values of AUC100%, EF1%, EF5%, sensitivity, and specificity are 0.93; 34.0%; 6.0%; 1.00; 0.79 respectively. The virtual screening results using the optimized model were evaluated based on Lipinski’s Rule of Five with KNIME. Eleven natural compounds from HerbalDB that may be developed into anti-PCSK9 therapy in oral dosage form were obtained, including morindone, gentisin, mesuaxanthone A, beta-phenethylamine, brazilin, pterofuran, n-cis-feruloyltyramine, bethanidine, 6-methoxykaempferol, gartanin, and alizarin."

"The lock-and-key principle formulated by Emil Fischer as early as the end of the 19th century has still not lost any of its significance for the life sciences. The basic aspects of ligand-protein interaction may be summarized under the term 'molecular recognition' and concern the specificity as well as stability of ligand binding. Molecular recognition is thus a central topic in the development of active substances, since stability and specificity determine whether a substance can be used as a drug. Nowadays, computer-aided prediction and intelligent molecular design make a large contribution to the constant search for, e. g., improved enzyme inhibitors, and new concepts such as that of pharmacophores are being developed."