Molecular Characterization of Mosquitocidal Toxin (Surface Layer Protein, SLP) from Bacillus cereus VCRC B540 Chinnasamy Mani 1 & Jeyaperumal Selvakumari 1 & YeonSoo Han 2 & YongHun Jo 2 & Krishnaraj Thirugnanasambantham 1 & Somaiah Sundarapandian 3 & Subbiah Poopathi 1 Received: 24 March 2017 / Accepted: 13 September 2017 / Published online: 26 September 2017 # Springer Science+Business Media, LLC 2017 Abstract A marine Bacillus cereus (VCRC B540) with mosquitocidal effect was recently reported from red snapper fish (Lutjanus sanguineous) gut and surface layer protein (S-layer protein, SLP) was reported to be mosquito larvicidal factor. In this present study, the gene encoding the surface layer protein was amplified from the genomic DNA and functionally characterized. Amplification of SLP-encoding gene revealed 1,518 bp PCR product, and analysis of the sequence revealed the presence of 1482 bp open reading frame with coding capacity for a polypeptide of 493 amino acids. Phylogenetic analysis revealed with homology among closely related Bacillus cereus groups of organisms as well as Bacillus strains. Removal of nucleotides encoding signaling peptide revealed the functional cloning fragment of length 1398 bp. Theo- retical molecular weight (51.7 kDa) and isoelectric point (5.99) of the deduced functional SLP protein were predicted using ProtParam. The amplified PCR product was cloned into a plasmid vector (pGEM-T), and the open reading frame free off signaling peptide was subsequently cloned inpET-28a(+) and expressed in Escherichia coli BL21 (DE3). The isopropyl-β-D-thiogalactopyranoside (IPTG)-induced recombinant SLP was Appl Biochem Biotechnol (2018) 184:1094–1105 DOI 10.1007/s12010-017-2602-5 Electronic supplementary material The online version of this article (https://doi.org/10.1007/s12010-017-2602-5) contains supplementary material, which is available to authorized users. * Subbiah Poopathi Subbiahpoopathi@rediffmail.com 1 Vector Control Research Centre (Indian Council of Medical Research), Department of Health Research, Ministry of Health and Family Welfare, Indira Nagar, Puducherry 605006, India 2 Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Science, Chonnam National University, Gwangju, Republic of Korea 3 Department of Ecology and Environmental Sciences, School of Life-Sciences, Pondicherry University, Puducherry 605014, India