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ROGA FLORIDA KEMBAREN
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The Role of the First 14 Amino Acids of Mature M1 Protein of Streptococcus pyogenes on Fibronectin-Binding Activity and Dimer Formation ROGA FLORIDA KEMBAREN; ADAM REZA GANJARA; VALENTINA YURINA; DEBBIE SOEFIE RETNONINGRUM
Microbiology Indonesia Vol. 4 No. 1 (2010): April 2010
Publisher : Indonesian Society for microbiology

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1672.376 KB) | DOI: 10.5454/mi.4.1.5

Abstract

Streptococcus pyogenes is one of the most important human pathogens which express a multi-facet of virulence factors on its cell surface. One of the virulence factors that has been intensively-studied is the M protein that binds several human proteins. M1 protein, a member of the M protein family, was previously found to bind human fibronectin (Fn), an activity that is responsible for bacterial internalization. A structural study showed that this protein consists of four regions: A, B, S, and C. The study was intended to investigate the role of the first 14 amino acid residues located at the non-helical region of M1 protein in binding Fn, and its ability to form a dimer. The DNA fragment encoding for the ABS protein lacking its first 14 amino acids (ABSD14aa) was cloned into pET-16b, overexpressed in Escherichia coli BL21(DE3), and the protein was purified by affinity chromatography. The purified protein was characterized by sodium dodecyl sulphate polyacrylamide gel electrophoresis and the Fn-binding activtiy was assayed by enzyme linked immunosorbent assay. The result indicated that the M1 lacking its first 14 amino acids retains its dimerization and Fn-binding activities.
Peningkatan Literasi STEM melalui Del Mathematics and Science Competition Bidang Kimia Arianti, Santi Febri; Kembaren, Roga Florida; Ronauli Silalahi, Fitriani Tupa; Gurning, Kartini Florensya; Sihombing, Lasro Setia
Lebah Vol. 18 No. 2 (2025): Maret: Pengabdian
Publisher : IHSA Institute

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Abstract

Kompetisi sains dan matematika memiliki peran penting dalam mendukung literasi STEM (Science, Technology, Engineering, and Mathematics), terutama di wilayah dengan akses pendidikan terbatas. Artikel ini menganalisis Del Mathematics and Science Competition (DMSC) bidang kimia, yang menggunakan format kompetisi hibrida untuk menjangkau siswa dari berbagai latar belakang geografis di Sumatra Utara. Kegiatan ini dirancang untuk meningkatkan pemahaman konsep kimia seperti struktur atom, ikatan kimia, dan termodinamika, sekaligus memotivasi siswa untuk melanjutkan pendidikan di bidang STEM. Dari 485 peserta yang mendaftar, 100 siswa mengikuti kompetisi bidang kimia pada putaran awal daring, dan 25 siswa terbaik melanjutkan ke putaran final luring. Hasil menunjukkan peningkatan rata-rata nilai peserta dari 50,5 menjadi 70,2, mencerminkan efektivitas kompetisi dalam meningkatkan pemahaman materi. Survei juga mencatat peningkatan minat siswa terhadap STEM, dari 60% sebelum kompetisi menjadi 85% setelah kegiatan. Temuan ini mendukung efektivitas format hibrida yang inklusif dalam memberikan pengalaman belajar bermakna dan mengatasi tantangan aksesibilitas pendidikan. Saran untuk pengembangan kegiatan ke depan mencakup peningkatan dukungan teknologi dan penambahan komponen pelatihan untuk memperkuat dampak kompetisi
EFFECT OF STORAGE TIME VARIATION OF ANDALIMAN FRUIT ON FREE RADICAL SCAVENGING AND PROLIFERATION INHIBITION ON MCF-7 CELLS Rosidah, Idah; Kusumastuti, Siska Andrina; Simanungkalit, Grace Sophiwati; Rahayu, Maya Damayanti; Nuralih, Nuralih; Martgrita, Merry Meryam; Kembaren, Roga Florida; Chaidir, Chaidir; Sunaryanto, Rofiq; Wibowo, Agung Eru
Berita Biologi Vol 23 No 2 (2024): Berita Biologi
Publisher : BRIN Publishing (Penerbit BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/beritabiologi.2024.3334

Abstract

Andaliman (Zanthoxylum acanthopodium D.C) is a plant widely used by the Batak people in North Sumatera. Several studies demonstrated that Andaliman fruit exhibits antioxidant activities and cytotoxic effects on cancer cells. Quality of Andaliman fruit could affected by post-harvest process including storage time. This research aims to analyze the compound, antioxidant activity and proliferation inhibition on MCF-7 cells of Andaliman fruit extracts (AFE) stored at varying storage time. A series of fresh 250 g Andaliman fruit sealed in a closed container and stored in the oven at 30ºC. After storage at 0, 24, 48, 72, 96, 120 and 144 hours, Andaliman fruit macerated using methanol and obtained successive extract yields of 4.12; 3.70; 12.79; 8.17; 8.15; 3.7 and 2.21. These extracts were analyzed for total phenolic, total flavonoids, free radical scavenging activity and proliferation inhibition on MCF-7 cells. The chemical compound analysis of AFE was performed by ultra performance liquid chromatography (UPLC). Results showed that the AFE stored at zero hours had higher total phenol content (47.32 mg gallic acid equivalent (GAE)/g of extract) and free radical scavenging activity (50.38%) at 500 µg/mL significantly compared to other extracts. The total flavonoid content of all extracts showed no difference level except for the extract at 120 hours of storage. The proliferation inhibition test on MCF-7 cells at 100 µg/mL showed that AFE stored at 72, 96 and 144 hours could inhibit MCF-7 cells above 50%. The storage time variation of Andaliman fruit may affect the total phenolic and flavonoid content, and also activity of free radical scavenging and proliferation inhibition on MCF-7. The UPLC analysis founded the major compound of AFE was predicted as α-sanshool. Analysis of chemicals substance in Andaliman fruit with varying of storage time need to be conducted to evaluated alteration of secondary metabolites contained in Andaliman fruit.
PROTEASE FROM Styrax paralleloneurum LEAVES AND ITS THROMBOLYTIC ACTIVITY ASSAY Sinaga, Ester Rosdiana; Martgrita, Merry Meryam; Kembaren, Roga Florida
Berita Biologi Vol 24 No 2 (2025): Berita Biologi
Publisher : BRIN Publishing (Penerbit BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/berita_biologi.2025.9145

Abstract

Thrombotic disease is one of the leading causes of death worldwide and enzymatic thrombolytic therapy remains the best way to achieve recanalization. Enzymatic thrombolytic agents used today have undesirable side effects, and some are expensive. Research for herbal protease enzymes was conducted because plant drugs are known to be safer. This study aimed to obtain protease enzymes from frankincense leaves and to test their thrombolytic activity. Enzyme concentration was determined by the Bradford method, and the results showed that the highest enzyme concentration was 1.6812 g/μL at 40% ammonium sulfate fraction. A quantitative assay of protease activity using Folin & Ciocalteu's phenol reagent and casein as substrate showed that 1.2609 mg of enzyme hydrolyzed 32.5 mg of casein and released 0.0980 mg of L-tyrosine. The fibrinogenolytic activity of protease against human fibrinogen tested by SDS-PAGE showed that the protease could hydrolyze fibrinogen γ-chain within 0 minutes and β-chain within 60 minutes, while α-chain could not be hydrolyzed until 720 minutes. The inhibitor effect assay showed that the protease was a serine protease. This study concluded that the protease enzyme from frankincense leaves has the potential to be used as a thrombolytic agent. 
Co-Authors ADAM REZA GANJARA Agung Eru Wibowo Arianti, Santi Febri Chaidir Chaidir DEBBIE SOEFIE RETNONINGRUM Fitriani Tupa R Silalahi Gurning, Kartini Florensya Idah Rosidah Martgrita, Merry Meryam Nuralih Nuralih, Nuralih Rahayu, Maya Damayanti Rofiq Sunaryanto Sihombing, Lasro Setia Simanungkalit, Grace Sophiwati Sinaga, Ester Rosdiana Siska Andrina Kusumastuti VALENTINA YURINA