Analisis Gen Tox Corynebacterium Diphtheriae Penyebab Difteri di Beberapa Wilayah Indonesia

Diphtheria is a vaccine-preventable disease. The clinical features and complications of diphtheria are associated with toxins produced by the causative bacteria. Diphtheria toxin synthesis is encoded by tox gene. This study aimed to provide an overview of the DNA sequences of the tox gene of Corynebacterium diphtheriae causing diphtheria in several region of Indonesia. A total of 65 Corynebacterium diphtheriae isolated from several provinces in Indonesia (2010-2017) were used as samples. Isolates recultured on blood agar medium (BA), incubated at 37 0 C overnight. DNA extraction conducted using the QiaAmp DNA Mini Kit. The DNA sequencing was carried out using the Whole Genome Sequencing (WGS) approach. The data conversion and analysis conducted using U-gene and BioEdit programs. Examination of 65 isolate C. diphtheriae with 1683 bp of tox gene sequences showed that there are 3 patterns of gene sequences with 3 mutation site. All mutations were silent mutation. The mutation sites were also not commonly used as 3’end binding site of the PCR primer. We concluded that tox gene of C. diphtheriae that causes diphtheria in some provinces in Indonesia have limited variations and these variations do not encode amino acid changes. This indicates that the vaccines used in Indonesia are still in accordance with the variations in circulating bacteria and PCR can be used for screening and predicting the toxigenicity of diphtheria-causing bacteria. Keywords: C. diphtheriae, gene tox, diphtheria, Indonesia Abstrak Difteri merupakan salah satu penyakit yang dapat dicegah dengan imunisasi (PD3I). Gambaran klinis dan komplikasi difteri dikaitkan dengan toksin yang diproduksi oleh bakteri penyebab. Sintesis toksin difteri dikode oleh gen tox. Penelitian ini bertujuan untuk memberikan gambaran sekuens DNA gen tox Corynebacterium diphtheriae penyebab difteri di beberapa wilayah Indonesia. Sebanyak 65 isolat C. diphtheriae tersimpan milik Badan Litbangkes yang diisolasi dari beberapa wilayah Indonesia tahun 2010- 2017 dijadikan sebagai sampel. Rekultur dilakukan pada medium agar darah (BA), diinkubasi pada suhu 37 o C selama sehari semalam. Ekstraksi DNA menggunakan kit QiaAmp DNA Minikit. Sekuensing DNA dilakukan dengan pendekatan Whole Genome Sequencing (WGS). Konversi dan analisis data menggunakan program U-gene dan BioEdit.Pemeriksaan 65 isolat C. diphtheriae dengan 1683 bp sekuens gen tox menunjukkan ada 3 pola sekuens gen dengan 3 lokasi mutasi. Seluruh mutasi bersifat sil