title: Identification and characterization of the insecticidal toxin "makes caterpillars floppy" in Photorhabdus temperata M1021 using a cosmid library.
abstract: Photorhabdus temperata is an entomopathogenic enterobacterium; it is a nematode symbiont that possesses pathogenicity islands involved in insect virulence. Herein, we constructed a P. temperata M1021 cosmid library in Escherichia coli XL1-Blue MRF` and obtained 7.14 × 105 clones. However, only 1020 physiologically active clones were screened for insect virulence factors by injection of each E. coli cosmid clone into Galleria mellonella and Tenebrio molitor larvae. A single cosmid clone, PtC1015, was consequently selected due to its characteristic virulent properties, e.g., loss of body turgor followed by death of larvae when the clone was injected into the hemocoel. The sequence alignment against the available sequences in Swiss-Prot and NCBI databases, confirmed the presence of the mcf gene homolog in the genome of P. temperata M1021 showing 85% homology and 98% query coverage with the P. luminescens counterpart. Furthermore, a 2932 amino acid long Mcf protein revealed limited similarity with three protein domains. The N-terminus of the Mcf encompassed consensus sequence for a BH3 domain, the central region revealed similarity to toxin B, and the C-terminus of Mcf revealed similarity to the bacterial export domain of ApxIVA, an RTX-like toxin. In short, the Mcf toxin is likely to play a role in the elimination of insect pests, making it a promising model for use in the agricultural field.
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. ihsanknu@gmail.com.
authors.forename: Ihsan
authors.initials: I
authors.lastname: Ullah
authors.affiliation: Food and Biological Resources Examination Division, Korean Intellectual Property Office, Daejeon 302-701, Korea. jangek38@korea.kr.
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Jang
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. mslily87@nate.com.
authors.forename: Min-Sung
authors.initials: MS
authors.lastname: Kim
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. kormidas@naver.com.
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Shin
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. parkgun00700@nate.com.
authors.forename: Gun-Seok
authors.initials: GS
authors.lastname: Park
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. rahimkhan_84@yahoo.com.
authors.forename: Abdur Rahim
authors.initials: AR
authors.lastname: Khan
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. jjanghsj@naver.com.
authors.forename: Sung-Jun
authors.initials: SJ
authors.lastname: Hong
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. bkjung@knu.ac.kr.
authors.forename: Byung-Kwon
authors.initials: BK
authors.lastname: Jung
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. chjba@hanmail.net.
authors.forename: JungBae
authors.initials: J
authors.lastname: Choi
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. wofoddl313@naver.com.
authors.forename: YeongJun
authors.initials: Y
authors.lastname: Park
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. yun@knu.ac.kr.
authors.forename: Yunyoung
authors.initials: Y
authors.lastname: Kwak
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Korea. jhshin@knu.ac.kr.
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Shin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity; D001427:Bacterial Toxins / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity; D003360:Cosmids; D004926:Escherichia coli / Q000235:genetics; D007306:Insecticides / Q000302:isolation & purification / Q000633:toxicity; D007814:Larva / Q000187:drug effects; D008969:Molecular Sequence Data; D009036:Moths / Q000187:drug effects; D020637:Photorhabdus; D010802:Phylogeny; D013712:Tenebrio / Q000187:drug effects; D037521:Virulence Factors / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D007306:Insecticides; D037521:Virulence Factors