Analisis Bioinformatika dan Ekspresi Protein Rekombinan Hemagglutinin Domain Globular dari Virus H5N1 Indonesia pada Eschericia coli BL21 (DE3) sebagai Komponen Vaksin Subunit Influenza

Flu burung merupakan salah satu penyakit zoonosis yang patut diwaspadai di Indonesia, khususnya galur High Pathogenic Avian Influenza (HPAI) karena dapat mematikan jika menular kepada manusia. Penggunaan vaksin influenza pada unggas, merupakan langkah preventif terhadap evolusi virus yang berbahaya dan juga penyebarannya. Selama ini, Indonesia masih menggunakan seed vaksin impor yang berasal dari luar Indonesia. Namun, karena Indonesia merupakan negara yang berada di garis khatulistiwa, karakteristik virus bisa berbeda dengan virus dari nothern-hemispere maupun southern-hemispere. Mengingat hal tersebut, Indonesia harus mengembangkan vaksin influenza menggunakan galur virus lokal. Berbeda dengan vaksin whole virus, vaksin rekombinan memiliki keunggulan dari sisi kemurnian, kecepatan produksi, dan kesesuaian galur terhadap virus yang beredar saat diperlukan. Penelitian ini bertujuan untuk menganalisis sekuen hemagglutinin (HA) Indonesia dengan strain lainnya serta mengekspresikkan protein HA1 rekombinan pada Escherichia coli BL21 (DE3). Galur yang digunakan pada studi ini berasal dari virus H5N1 (A/Indonesia/05/05), khususnya bagian domain globular dari HA1. Sekuen HA1 bervariasi antara strain Indonesia dengan nothern-hemispere maupun southern-hemispere dan merupakan protein yang terpapar ke luar virus. Gen HA1 disisipkan pada vektor pET-28a, kemudian plasmid diisolasi menggunakan meoe manniatis, setelah itu diekspresikan dengan induksi 1 mM IPTG selama 4 jam. Protein HA1 telah berhasil diekspresikan secara intraseluler dan telah dikonfirmasi pada berat molekul 40 kDa menggunakan SDS-PAGE. Penelitian ini dapat digunakan untuk mengembangkan vaksin subunit yang lebih spesifik terhadap virus yang beredar di lapangan.

Angicin, a novel bacteriocin of Streptococcus anginosus

As a conserved defense mechanism, many bacteria produce antimicrobial peptides, called bacteriocins, which provide a colonization advantage in a multispecies environment. Here the first bacteriocin of Streptococcus anginosus, designated Angicin, is described. S. anginosus is commonly described as a commensal, however it also possesses a high pathogenic potential. Therefore, understanding factors contributing to its host colonization and persistence are important. A radial diffusion assay was used to identify S. anginosus BSU 1211 as a potent bacteriocin producer. By genetic mutagenesis the background of bacteriocin production and the bacteriocin gene itself were identified. Synthetic Angicin shows high activity against closely related streptococci, listeria and vancomycin resistant enterococci. It has a fast mechanism of action and causes a membrane disruption in target cells. Angicin, present in cell free supernatant, is insensitive to changes in temperature from − 70 to 90 °C and pH values from 2 to 10, suggesting that it represents an interesting compound for potential applications in food preservation or clinical settings.

Morphological and Molecular Identification of Fungi Causing Canker Disease on Melia Azidarch Trees in Some Regions of Mosul Provinces, Iraq

The aim of this study was to identify the fungi associated with canker disease on Melia azidarch trees inside Mosul University campus and the presidential palaces regions in Mosul Province, Iraq. Results of isolation showed the presenting of the fungi (Nattrassia mangiferae, Neoscylitidium dimidiatum Penz., Fusarium graminearium Schw., Alternaria brassicicola Schw., Aspergillus sp. and Penecillium sp.), which accompanied with the samples displayed cankering symptoms during the period from April to December/2020, the maximum of dominance was 85% for the fungus Neoscylitidium dimidiatum in August, while the lowest was 49% in April for the same year, followed by Fusarium graminearium with 38% in December, while the lowest percentage was 4% in October, then Alternaria brassicicola Schw. was 25% in April and the lowest value was 0% in August, followed by Aspergillus sp. and Penecillium sp. with low isolation percentages the maximum of which 25% and the lowest is 0% in August. When studying the pathogenicity of the isolated fungi, the results showed a high pathogenic effect in terms the length, diameter and the area of cankers symptom. Based on the results of the molecular diagnosis, the morphological identification was confirmed and it was clear that Fusarium austroamericanum, detection is considered the first record of this fungus in Iraq Melia azidarch trees.

Angicin, a novel bacteriocin of Streptococcus anginosus

As a conserved defense mechanism, many bacteria produce antimicrobial peptides, called bacteriocins, which give a colonization advantage in a multispecies environment. Here the first bacteriocin of Streptococcus anginosus, designated Angicin, is described. S. anginosus is commonly described as a commensal, however it also possesses a high pathogenic potential. Therefore, understanding factors contributing to its host colonization and persistence are important. A radial diffusion assay was used to identify S. anginosus BSU 1211 as a potent bacteriocin producer. By genetic mutagenesis the background of bacteriocin production and the bacteriocin gene itself were identified. Synthetic Angicin shows high activity against closely related streptococci, listeria and vancomycin resistant enterococci. It has a fast mechanism of action and causes a membrane disruption in target cells. Angicin, present in cell free supernatant, is insensitive to changes in temperature from −70 to 90 °C and pH values from 2-10, suggesting that it represents an interesting compound for potential applications in food preservation or clinical settings.

Laporan Kasus Avian Influenza di Dusun Cabean, Kelurahan Mangunsari, Kecamatan Sidomukti, Kota Salatiga Tahun 2019

Virus Avian Influenza (AI) dibedakan menjadi Low Pathogenic Avian Influenza (LPAI) dan High Pathogenic Avian Influenza (HPAI) dimana pada HPAI ditunjukkan dengan tingkat kematian unggas yang mencapai 100% dalam waktu yang singkat. Tujuan dari penelitian terhadap kematian unggas di Cabean, kelurahan Mangunsari, Kecamatan Sidomukti, Kota Salatiga adalah untuk mengidentifikasi penyebab kematian dan menentukan tindakan pengendalian. Observasi dilakukan pada tanggal 29 Juli 2019 hingga 3 Agustus 2019 dan analisis data dilakukan secara deskriptif. Informasi kematian mendadak pada unggas dilaporkan pemilik pada 29 Juli 2019. Dalam satu minggu kematian ayam kampung mencapai 38,75%, itik manila (entok) mencapai 90% dan angsa mencapai 100%. Dari hasil pemeriksaan berdasarkan informasi, nekropsi, rapid test dan laboratorium, dapat disimpulkan bahwa kematian mendadak pada unggas yang terjadi di Cabean disebabkan oleh virus Avian Influenza. Hasil investigasi diharapkan mampu memberikan kejelasan penyebab kematian unggas dan pemahaman kepada masyarakat terutama peternak unggas mengenai virus Avian Influenza, tindak pencegahan dan penanggulangannya.

Crystal structure of inhibitor-bound human MSPL that can activate high pathogenic avian influenza

Infection of certain influenza viruses is triggered when its HA is cleaved by host cell proteases such as proprotein convertases and type II transmembrane serine proteases (TTSP). HA with a monobasic motif is cleaved by trypsin-like proteases, including TMPRSS2 and HAT, whereas the multibasic motif found in high pathogenicity avian influenza HA is cleaved by furin, PC5/6, or MSPL. MSPL belongs to the TMPRSS family and preferentially cleaves [R/K]-K-K-R↓ sequences. Here, we solved the crystal structure of the extracellular region of human MSPL in complex with an irreversible substrate-analog inhibitor. The structure revealed three domains clustered around the C-terminal α-helix of the SPD. The inhibitor structure and its putative model show that the P1-Arg inserts into the S1 pocket, whereas the P2-Lys and P4-Arg interacts with the Asp/Glu-rich 99-loop that is unique to MSPL. Based on the structure of MSPL, we also constructed a homology model of TMPRSS2, which is essential for the activation of the SARS-CoV-2 spike protein and infection. The model may provide the structural insight for the drug development for COVID-19.

Nanobodies mapped to cross-reactive and divergent epitopes on A(H7N9) influenza hemagglutinin using yeast display

Influenza H7N9 virus continues to cause infections in humans and represents a significant pandemic risk. During the most recent 5th epidemic wave in 2016/17 two distinct lineages with increased human infections and wider geographical spread emerged. In preparation for any future adaptations, broadly reactive antibodies against H7N9 are required for surveillance, therapy and prophylaxis. In this study we have isolated a panel of nanobodies (Nbs) with broad reactivity across H7 influenza strains, including H7N9 strains between 2013 and 2017. We also describe Nbs capable of distinguishing between the most recent high and low pathogenicity Yangtze River Delta lineage H7N9 strains. Nanobodies were classified into 5 distinct groups based on their epitope footprint determined using yeast display and mutational scanning. The epitope footprint of Nbs capable of distinguishing high pathogenic (HP) A/Guangdong/17SF003/2016 from low pathogenic (LP) A/Hong Kong/125/2017 (H7N9) were correlated to natural sequence divergence in the head domain at lysine 164. Several Nbs binding to the head domain were capable of viral neutralisation. The potency of one nanobody NB7-14 could be increased over 1000-fold to 113 pM by linking two Nbs together. Nbs specific for distinct epitopes on H7N9 may be useful for surveillance or therapy in human or veterinary settings.