Occurrence of Bacillus species on evergreen oak leaves

Abstract

Thirty-five spore-forming bacilli were isolated from evergreen oak leaves at four stages (one-year-old and two-year-old leaves, upper layer and underlayer litter leaves) and over the four seasons within one year. These isolates, plus five reference strains, were characterized morphologically and physiologically by a total of 100 tests and genetically by DNA/DNA hybridization. Phenotypic similarities of all strains were determined by numerical taxonomy, with the unweighted average linkage (UPGMA) algorithm and simple matching (SsM) and Jaccard (S j) coefficients used as measures for similarity. Three groups (A to C) were defined at a similarity level of 71% (SsM) or 57% (S j). They contained leaf isolates phenotypically related to Bacillus cereus, B. pumilus and B. circulans species respectively. The majority of the leaf isolates were assigned to B. cereus (34%) and B. pumilus (63%). DNA/DNA hybridization also discriminated three groups (genomic groups 1, 2 and unclassified strains) which presented a good correlation with the numerical analysis. Yet, DNA/DNA hybridization grouping revealed a higher degree of discrimination by defining four subgroups (la, lb, 2a and 2b). Genomic subgroup la contained leaf isolates belonging to the B. cereus species; isolates from genomic subgroup lb belonged to B. mycoides species and isolates from genomic subgroup 2a belonged to B. pumilus species. Subgroup 2b consisted of a new genomic subspecies of B. pumilus which exhibited a degree of homology ranging from 53 to 64% with the B. pumilus type strain and a coefficient of divergence (ATm) ranging from 5.5 to 7°C. The different genomic groups presented different substrate metabolism capacities and a different spatial distribution on evergreen oak leaves. B. cereus strains (group 1) were predominantly located on litter leaves whereas B. pumilus strains (group 2) were found on the phyllosphere. In contrast with group 1, group 2 was able to metabolize some sugars and pectin, while group 1 isolates were able to hydrolyze starch and glycogen. Thus, our hypothesis is that group 1 succeeds group 2 when the leaves are littered.

Diversity of Bacterial Communities in Container Habitats of Mosquitoes

“…Bacteria in the phylum Bacteriodes accounted for 29 (32.2%) of 90 sequences in container habitats that we sampled, and Flavobacteria (7.7% of band sequences) was the most commonly detected genus. The genus Bacillus comprised a small number (4.4%) of OTUs, which is surprising since sporeforming bacilli are common on the surface of green and senescent oak leaves [6], which were common in the study area.…”

Epiphytic microorganisms on strawberry plants (Fragaria ananassa cv. Elsanta): identification of bacterial isolates and analysis of their interaction with leaf surfaces

“…Fa7 showed 99.9% identity with Bacillus cereus . B. cereus has been reported in the phyllosphere of Quercus ilex [24]. Fa25 had 100% identity with Bacillus weihenstephanensis , a psychrotolerant species in alpine soil [25] and a Bacillus mycoides strain.…”

“…Fa25 had 100% identity with Bacillus weihenstephanensis , a psychrotolerant species in alpine soil [25] and a Bacillus mycoides strain. B. mycoides was found in the phyllosphere of Malus × domestica [26], S. tuberosum [22] and Q. ilex [24]. Fa29 showed 99.7% identity with Bacillus sp.…”

Draft Genome Sequence of Bacillus thuringiensis Strain BrMgv02-JM63, a Chitinolytic Bacterium Isolated from Oil-Contaminated Mangrove Soil in Brazil

“…These enzymes are widely distributed in nature, being produced by a large variety of chitin-degrading organisms, including bacteria, fungi, insects, plants, and animals ( 1 ). The Gram-positive aerobic/facultative anaerobic endospore-forming bacterium Bacillus thuringiensis is commonly found in soils and estuarine sediments, as well as in association with plant roots ( 2 , 3 ). B. thuringiensis strain BrMgv02-JM63 was originally isolated from oil-contaminated mangrove soil located in the city of Bertioga, São Paulo, Brazil (23°53′49″S, 46°12′28″W).…”