School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK.
Division of Nematology, Indian Agricultural Research Institute, New Delhi, India.
J Appl Microbiol. 2022 Jun;132(6):4371-4387. doi: 10.1111/jam.15522. Epub 2022 Mar 22.
Phytonematodes are a constraint on crop production and have been controlled using nematicides; these are highly toxic and legislation in Europe and elsewhere is prohibiting their use and alternatives are being sought. Pasteuria penetrans is a hyperparasitic bacterium that form endospores and have potential to control root-knot nematodes (Meloidogyne spp.), but their attachment to the nematode cuticle is host-specific. Understanding host specificity has relied upon endospore inhibition bioassays using immunological and biochemical approaches. Phylogenetic analysis of survey sequences has shown P. penetrans to be closely related to Bacillus and to have a diverse range of collagen-like fibres which we hypothesise to be involved in the endospore adhesion. However, due to the obligately hyperparasitic nature of Pasteuria species, identifying and characterizing these collagenous-like proteins through gain of function has proved difficult and new approaches are required.
Using antibodies raised to synthetic peptides based on Pasteuria collagen-like genes we show similarities between P. penetrans and the more easily cultured bacterium Bacillus thuringiensis and suggest it be used as a gain of function platform/model. Using immunological approaches similar proteins between P. penetrans and B. thuringiensis are identified and characterized, one >250 kDa and another ~72 kDa are glycosylated with N-acetylglucosamine and both of which are digested if treated with collagenase. These treatments also affected endospore attachment and suggest these proteins are involved in adhesion of endospores to nematode cuticle.
There are conserved similarities in the collagen-like proteins present on the surface of endospores of both P. penetrans and B. thuringiensis.
As B. thuringiensis is relatively easy to culture and can be transformed, it could be developed as a platform for studying the role of the collagen-like adhesins from Pasteuria in endospore adhesion.
植物线虫是作物生产的一个限制因素，已经使用杀线虫剂进行了控制；这些药剂毒性很高，欧洲和其他地方的法规正在禁止它们的使用，正在寻找替代品。多粘类芽孢杆菌是一种超寄生细菌，它形成内生孢子，有可能控制根结线虫（Meloidogyne 属），但它们对线虫表皮的附着是宿主特异性的。对宿主特异性的理解依赖于使用免疫学和生化方法进行内生孢子抑制生物测定。调查序列的系统发育分析表明，多粘类芽孢杆菌与芽孢杆菌密切相关，并且具有广泛的胶原样纤维，我们假设这些纤维与内生孢子的附着有关。然而，由于多粘类芽孢杆菌属的专性超寄生性质，通过获得功能来鉴定和表征这些胶原样蛋白已被证明很困难，需要新的方法。
使用针对基于多粘类芽孢杆菌胶原样基因的合成肽产生的抗体，我们表明多粘类芽孢杆菌与更容易培养的细菌苏云金芽孢杆菌之间存在相似性，并建议将其用作获得功能的平台/模型。使用免疫学方法，鉴定和表征了多粘类芽孢杆菌和苏云金芽孢杆菌之间的相似蛋白，一种>250 kDa，另一种~72 kDa 被 N-乙酰葡萄糖胺糖基化，两者都被胶原酶处理消化。这些处理还影响了内生孢子的附着，表明这些蛋白参与了内生孢子与线虫表皮的附着。
多粘类芽孢杆菌和苏云金芽孢杆菌内生孢子表面存在保守的胶原样蛋白相似性。
由于苏云金芽孢杆菌相对容易培养并且可以转化，因此它可以被开发为研究多粘类芽孢杆菌内生孢子附着中胶原样黏附素作用的平台。
