Sains Malaysiana 50(6)(2021): 1651-1662

http://doi.org/10.17576/jsm-2021-5006-12

Toxins of Foodborne Pathogen Bacillus cereus and the Regulatory Factors Controlling the Biosynthesis of Its Toxins

(Toksin daripada Patogen Bawaan Makanan Bacillus cereus dan Faktor Kepengawalaturan yang Mengawal Biosintesis Toksinnya)

YUGENRAJ NAVANEETHAN¹, MOHD ESAH EFFARIZAH¹* & NORLI ISMAIL²

¹Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia

²Environmental Technology Division, School of Industrial Technology, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia

Diserahkan: 20 Mei 2020/Diterima: 9 Oktober 2020

ABSTRACT

Bacillus cereus is a versatile organism which causes two distinct types of food poisoning by producing toxins. Toxin formation in B. cereus is very much a complex process involving co-regulation of multiple genes exerting control at transcriptional, translational and post-translational level and such regulations too are often influenced by extrinsic factors. A comprehensive understanding of such factors is very crucial for holistic approaches and strategies in order to minimise food poisoning risk. Hence, this review will focus on the intrinsic and extrinsic factors controlling toxin biosynthesis in B. cereus.

Keywords: Bacillus cereus; emetic toxin; enterotoxins; gastroenteritis; virulence genes

ABSTRAK

Bacillus cereus adalah organisma serba boleh yang menyebabkan dua jenis keracunan makanan yang berbeza dengan menghasilkan toksin. Pembentukan toksin dalam B. cereus merupakan satu proses yang sangat kompleks melibatkan pengawalaturan pelbagai gen yang menjalankan kawalan pada tahap transkripsi, translasi and pascatranslasi manakala pengawalaturan tersebut sering dipengaruhi oleh faktor ekstrinsik. Pemahaman yang komprehensif mengenai faktor tersebut adalah sangat penting untuk pendekatan dan strategi yang holistik bagi mengurangkan risiko keracunan makanan. Oleh itu, tinjauan ini akan memberi tumpuan pada faktor intrinsik dan ekstrinsik yang mengawal biosintesis toksin dalam B. cereus.

Kata kunci: Bacillus cereus; enterotoksin; gastroenteritis; gen kevirulenan; toksin emetik

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