Paenibacillus polymyxa (formerly known as Bacillus polymyxa) has been extensively studied for agricultural applications as a plant-growth-promoting rhizobacterium and is also an important biocontrol agent. Our team has developed the P. polymyxa strain HY96-2 from the tomato rhizosphere as the first microbial biopesticide based on P. polymyxa for controlling plant diseases around the world, leading to the commercialization of this microbial biopesticide in China. However, further research is essential for understanding its precise biocontrol mechanisms. In this paper, we report the complete genome sequence of HY96-2 and the results of a comparative genomic analysis between different P. polymyxa strains. The complete genome size of HY96-2 was found to be 5.75 Mb and 5207 coding sequences were predicted. HY96-2 was compared with seven other P. polymyxa strains for which complete genome sequences have been published, using phylogenetic tree, pan-genome, and nucleic acid co-linearity analysis. In addition, the genes and gene clusters involved in biofilm formation, antibiotic synthesis, and systemic resistance inducer production were compared between strain HY96-2 and two other strains, namely, SC2 and E681. The results revealed that all three of the P. polymyxa strains have the ability to control plant diseases via the mechanisms of colonization (biofilm formation), antagonism (antibiotic production), and induced resistance (systemic resistance inducer production). However, the variation of the corresponding genes or gene clusters between the three strains may lead to different antimicrobial spectra and biocontrol efficacies. Two possible pathways of biofilm formation in P. polymyxa were reported for the first time after searching the KEGG database. This study provides a scientific basis for the further optimization of the field applications and quality standards of industrial microbial biopesticides based on HY96-2. It may also serve as a reference for studying the differences in antimicrobial spectra and biocontrol capability between different biocontrol agents.

A method was developed for detection of Listeria monocytogenes by polymerase chain reaction amplification followed by agarose gel electrophoresis or dot blot analysis with a 32P-labeled internal probe. The technique identified 95 of 95 L. monocytogenes strains, 0 of 12 Listeria strains of other species, and 0 of 12 non-Listeria strains.

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Perception of information is of critical importance for aquatic activities; however, the complex underwater situation faces unique technical challenges to address. Thus, an underwater environment-incorporated sensing strategy, referred to as aquatic skin, has been introduced with multi-modality sensing capacities of contact pressure, tactile mapping, depth, temperature, and salinity in a flexible architecture. Remarkably, this has been all achieved by a multi-modality iontronic sensing principle in an all-in-one structural configuration, simplifying the sensor design, material preparation, device fabrication, and signal processing. Particularly, an inverse iontronic sensing mechanism, utilizing complementary elastomeric-electrode and environmental-electrode interfaces, is developed for contact pressure detection with exceptional resolution and hydraulic balance. Moreover, a hydrophobic ionic gel with adjustable surface morphologies has been developed as the functional sensing layer for all the units with long-term stability. Consequently, the aquatic skin can achieve sub-Pascal resolution of contact pressure detection (0.59 Pa), and sub-millimeter spatial resolution of tactile mapping (522 pts cm −2 ) over an extended range of depths (0-40 m), while the environmental influences can be spontaneously eliminated through a self-compensation process. The aquatic skin is applied toward several representative underwater scenes, including real-time monitoring of vital/environmental signals, tactile recognition of creatures, and biomechanical analysis of fish swimming.