Structure of the Lysinibacillus sphaericus Tpp49Aa1 pesticidal protein elucidated from natural crystals using MHz-SFX

Tpp49Aa1 from Lysinibacillus sphaericus is a Toxin_10 family protein that must interact with Cry48Aa1, a 3-domain crystal protein, to produce potent mosquitocidal activity, specifically against Culex quinquefasciatus mosquitoes. We use Culex cell lines to demonstrate for the first time transient detrimental effects of individual toxin components and widen the known target range of the proteins. MHz serial femtosecond crystallography at a nano-focused X-ray free electron laser allowed rapid and high-quality data collection to determine the Tpp49Aa1 structure at 2.2 Å resolution from the merged X-ray diffraction data. The structure revealed the packing of Cry49Aa1 within the natural nanocrystals isolated from sporulated bacteria, as a homodimer with a large intermolecular interface. We then modelled the potential interaction between Tpp49Aa1 and Cry48Aa1. The structure sheds light on natural crystallisation and, along with cell-based assays broadens our understanding of this two-component system.

Botanical Potency of Chromolaena odorata Linn (Hagonoy) as Mosquitocidal

Chromolaena odorata Linn is considered an environmental weed that is traditionally used as a treatment of numerous environmental conditions such as wound healing functions and amelioration of inflammation. In this study, Chromolaena odorata linn was discovered as an alternative and natural product of mosquitocide. Based on the results gathered and obtained the stem, leaves, and roots are proven to be effective to use rather than using only one part of the plant. Furthermore, the data gathered shows that it only took a small amount of time to kill the mosquito using all parts of the Chromolaena odorata linn extract. The mosquitocidal activity of Chromolaena odorata linn had shown its potential significance, eco-friendly, and cost-effective with the presence of botanical phytochemicals (alkaloids, cardiac glycosides, anthocyanin, tannin, and flavonoids) as a source of controlling the mosquito population Keywords: botanical potency, mosquitocidal, chromolaena odorata Linn, mosquitos.

Identification of entomopathogenic nematodes and their symbiotic bacteria in national parks of Thailand, and mosquitocidal activity of Xenorhabdus griffiniae against Aedes aegypti larvae

Summary Entomopathogenic nematodes (EPN) Steinernema and Heterorhabditis with symbionts with Xenorhabdus and Photorhabdus bacteria, respectively, are reported as biocontrol agents for insect control. The objectives of this study were to identify EPN and their symbiotic bacteria in national parks of Phitsanulok Province, Thailand, and to test how Xenorhabdus isolates attack Aedes aegypti larvae. We collected 810 soil samples from four national parks. The juvenile stage of EPN was isolated from soil samples using a baiting technique with Galleria mellonella followed by a White trap. Partial regions of 28S rDNA and internal transcript spacer were sequenced to identify EPN, and recA sequencing was used to discriminate between Xenorhabdus and Photorhabdus. We found that 74 of the 810 soil samples (9.1%) were positive for the EPN. The EPN were molecularly identified as S. surkhetense, S. longicaudum, H. indica and Heterorhabditis sp. SGmg3, and their symbiotic bacteria were identified as X. stockiae, X. griffiniae, X. indica, X. vietnamensis, P. luminescens subsp. akhurstii, and P. temperata subsp. temperata. Xenorhabdus griffiniae showed potential larvicidal activity against A. aegypti (91% mortality at 72 and 96 h after exposure). This study demonstrates the diversity of EPN and symbiotic bacteria in national parks of Thailand and the potential to use X. griffiniae as a biocontrol agent to kill A. aegypti larvae.