Kevin C. Failor

Ly.si.ni.ba.cil'lus. N.L. neut. n. lysinum lysine; L. masc. n. bacillus a small staff or rod; N.L. masc. n. Lysinibacillus lysine bacillus, referring to the presence of the Lys–Asp type of peptidoglycan in the cell wall. The genus Lysinibacillus was proposed in 2007 to describe a phylogenetic and physiological distinct group of Bacillaceae that exhibit an l ‐Lys‐ d ‐Asp (A4α) cell wall composition. Twenty‐one Lysinibacillus species were validly published between 2007 and 2018, and five former Bacillus species were moved to Lysinibacillus . Lysinibacillus boronitolerans serves as the type species. Lysinibacillus strains have been isolated from an impressive diversity of environments ranging from pristine and contaminated soils to plants, aquatic environments, indoor air, food, insects, animal waste, a cellular phone screen, and even an organic solvent. The genus is primarily Gram‐positive and aerobic with cells consisting in motile rods capable of forming terminally located bulging endospores. All species are catalase‐positive and typically have iso‐C _15:0 as the primary fatty acid and MK‐7 as the primary menaquinone system. Diphosphatidylglycerol and phosphatidylglycerol are the major polar lipids. The members of the genus Lysinibacillus cannot reduce nitrate, are unable to produce indole, and are incapable of utilizing 2‐ketogluconate, capric acid, d ‐arabinose, gentiobiose, indole, myo ‐inositol, stachyose, starch, β‐gentiobiose, and β‐methyl‐xyloside. While the Lysinibacillus genus is best known for a clonal lineage of mosquitocidal isolates because of their widespread use in mosquito control, Lysinibacillus strains also have potential in biotechnological applications and bioremediation because of their enzymatic capabilities and tolerance to a variety of pollutants. DNA G + C content (mol%) : 35–43.3. Type species : Lysinibacillus boronitolerans Ahmed, Yokota, Yamazoe and Fujiwara 2007, 1121 ^VP . Taxonomic and Nomenclature Notes: According to the List of Prokaryotic names with Standing in Nomenclature (LPSN), the taxonomic status of the genus Lysinibacillus is: correct name (last update, February 2025) ^* . LPSN classification: Bacteria / Bacillati / Bacillota / Bacilli / Caryophanales / Caryophanaceae / Lysinibacillus The genus Lysinibacillus can also be recovered in the Genome Taxonomy Database (GTDB) as g__Lysinibacillus (version v220) ^** . GTDB classification: d__Bacteria / p__Bacillota / c__Bacilli / o__Bacillales_A / f__Planococcaceae / g__Lysinibacillus ^* Meier‐Kolthoff et al. ( 2022 ). Nucleic Acids Res , 50 , D801 – D807 ; DOI: 10.1093/nar/gkab902 ^** Parks et al. ( 2022 ). Nucleic Acids Res , 50 , D785 – D794 ; DOI: 10.1093/nar/gkab776

On a subfreezing surface, nucleating embryos usually form as supercooled condensate that later freezes into ice, as opposed to desublimation. Ice nucleating proteins (INPs) have been widely used to quickly freeze existing supercooled water; however, nobody has studied how they might affect the initial mode of embryo formation. We show that INPs deposited on a substrate can switch the mode of embryo nucleation to desublimation, rather than supercooled condensation, beneath a critical temperature. By patterning a hydrophobic surface with an array of hydrophilic stripes, the INPs can be selectively deposited by evaporating water that exclusively spreads along the hydrophilic regions. The resulting array of desublimating ice stripes created dry zones free of condensation or frost in the intermediate areas, as the hygroscopic ice stripes served as overlapping humidity sinks.

A growing body of circumstantial evidence suggests that ice nucleation active (Ice⁺) bacteria contribute to the initiation of precipitation by heterologous freezing of super-cooled water in clouds. However, little is known about the concentration of Ice⁺ bacteria in precipitation, their genetic and phenotypic diversity, and their relationship to air mass trajectories and precipitation chemistry. In this study, 23 precipitation events were collected over 15 months in Virginia, USA. Air mass trajectories and water chemistry were determined and 33 134 isolates were screened for ice nucleation activity (INA) at −8 °C. Of 1144 isolates that tested positive during initial screening, 593 had confirmed INA at −8 °C in repeated tests. Concentrations of Ice⁺ strains in precipitation were found to range from 0 to 13 219 colony forming units per liter, with a mean of 384±147. Most Ice⁺ bacteria were identified as members of known and unknown Ice⁺ species in the Pseudomonadaceae, Enterobacteriaceae and Xanthomonadaceae families, which nucleate ice employing the well-characterized membrane-bound INA protein. Two Ice⁺ strains, however, were identified as Lysinibacillus, a Gram-positive genus not previously known to include Ice⁺ bacteria. INA of the Lysinibacillus strains is due to a nanometer-sized molecule that is heat resistant, lysozyme and proteinase resistant, and secreted. Ice⁺ bacteria and the INA mechanisms they employ are thus more diverse than expected. We discuss to what extent the concentration of culturable Ice⁺ bacteria in precipitation and the identification of a new heat-resistant biological INA mechanism support a role for Ice⁺ bacteria in the initiation of precipitation.

As part of an undergraduate microbiology course, a yellow–orange-pigmented, Gram-staining negative, rod-shaped, non-motile bacterial strain was isolated from a glass tank housing several red-spotted newts (Notophthalmus viridescens). The sequence of the 16S rRNA gene of this strain, designated KM^T, was 97.4–98.0 % similar to those of the type strains of Chryseobacterium luteum , C. shigense and C. vrystaatense , while the similarity levels for protein-coding genes were less than 94.7 % forrpoB, less than 92.1 % forgroELand less than 87.1 % forgyrB. These values are lower than for many other established distinct species. Polyphasic characterization and comparison to these relatives revealed that strain KM^Twas similar to other Chryseobacterium strains in that it contained MK-6 as its major respiratory quinone and phosphatidylethanolamine as the most abundant polar lipid, produced flexirubin-type pigments, oxidase and catalase and primarily contained the fatty acids iso-C_15 : 0, iso-C_17 : 1ω9c, iso-C_17 : 03-OH and summed feature 3 (comprising C_16 : 1ω6cand/or C_16 : 1ω7c). Based on the results of this study, strain KM^Trepresents a novel species, for which the nameChryseobacterium angstadtiisp. nov. is proposed. The type strain is KM^T( = ATCC BAA-2160^T = NRRL B-59516^T = KCTC 23297^T).

As part of an undergraduate microbiology course, a yellow–orange pigmented, Gram-staining negative, rod-shaped, non-motile bacterial strain, designated CTM^T, was isolated from a creek in North-central Pennsylvania during the winter of 2006. The 16S rRNA gene sequence of the strain showed ~97 % similarity to that ofChryseobacterium soldanellicolaPSD1-4^TandChryseobacterium soliJS6-6^T, while the protein-codinggyrBgene sequence of strain CTM^Tshowed Twas characterized and compared to these and other closely related species of the genusChryseobacterium. Strain CTM^Twas similar to other strains of the genusChryseobacteriumin that it contained MK-6 as its major respiratory quinone, produced flexirubin-type pigments, oxidase and catalase, hydrolysed DNA, gelatin and aesculin and contained the fatty acids iso-C_15 : 0, iso-C_17 : 1ω9c, iso-C_17 : 03-OH and summed feature 3 (C_16 : 1ω6c, C_16 : 1ω7cand/or iso-C_15 : 02-OH). Based on the results of this study, strain CTM^Trepresents a novel species of the genusChryseobacterium, for which the nameChryseobacterium piperisp. nov. is proposed. The type strain is CTM^T( = ATCC BAA-1782^T = CCUG 57707^T = JCM 15960^T = DSM 22249^T = KCTC 23267^T).