Juozas Raugalas

Bacillus butanolivorans sp. nov., a species with industrial application for the remediation of n-butanol.

Four bacterial strains, designated K9(T), K105, K1012A and K101, were isolated from soil in Lithuania. All these strains could use n-butanol as a sole carbon source. The strains grew in a medium containing 12-120 mM n-butanol. The strains were strictly aerobic, Gram-positive endospore-formers. The best growth was achieved at 25 degrees C and pH 7.0 in medium containing 1 % (w/v) NaCl. The strains showed identical profiles of 16S-23S rRNA internal transcribed spacer PCR and nearly identical 16S rRNA gene PCR-RFLP electrophoretic patterns and physiological characteristics, demonstrating their relationship at the species level. The cellular fatty acid profile of K9(T) consisted of significant amounts of the C(15) branched-chain fatty acids iso-C(15 : 0) (16.78 %) and anteiso-C(15 : 0) (45.80 %). The diagnostic cell-wall diamino acid was meso-diaminopimelic acid. The 16S rRNA gene sequence of K9(T) showed the highest similarity to the sequences of Bacillus simplex DSM 1321(T) and Bacillus muralis LMG 20238(T) (98.3 and 97.7 %, respectively). The DNA G+C content was 37.4 mol%. Studies of DNA-DNA relatedness, morphological, physiological and chemotaxonomic analyses and phylogenetic data based on 16S rRNA gene sequencing allowed strains K9(T), K105, K1012A and K101 to be described as members of a novel species of the genus Bacillus, for which the name Bacillus butanolivorans sp. nov. is proposed. The type strain is K9(T) (=DSM 18926(T) =LMG 23974(T)).

Paenibacillus tylopili sp.nov., a chitinolytic bacterium isolated from the mycorhizosphere of Tylopilus felleus

Two chitinolytic bacterial strains (designated MK2T and V7) were isolated from the mycorhizosphere of the fungus Tylopilus felleus. The strains were facultatively anaerobic G+ endospore formers. Physiological analysis and 16S rRNA gene PCR-RFLP assays revealed nearly identical profiles for both strains, demonstrating their relationship at the species level. Sequences specific for the genus Paenibacillus were found within the 16S rRNA gene sequence of the strain MK2T. The 16S rRNA gene sequence showed the highest similarity to the sequences of Paenibacillus amylolyticus, P. pabuli and P. xylanilyticus. DNA-DNA relatedness of the strain with the type strain of P. amylolyticus was 4.95 %, of P. pabuli 38.0 %, and of P. xylanilyticus 46.3 %, indicating no relatedness between MK2T and any of them at the species level. The most abundant fatty acids in strains MK2T and V7 were anteiso-C15:0, iso-C16:0, iso-C15:0 and n-C16:0. DNA-DNA relatedness, morphological, physiological and chemotaxonomic analyses, and phylogenetic data based on 16S rRNA gene sequencing made it possible to describe both strains as the novel species of the genus Paenibacillus, for which the name Paenibacillus tylopili is proposed, the type strain being MK2T (DSM 18927T, LMG 23975T).

Unusual intragenomic and interspecific variability of Geobacillus 16S-23S rRNA internal transcribed spacers

The aim of this study was to evaluate the inter-and intraspecific as well as intragenomic variability of Geobacillus 16S–23S rRNA internal transcribed spacers without tRNA genes and to compare these sequences with sequences bearing tRNA genes. In this study the structural analysis was performed in a unique way because the length and the sequence of the structural blocks were adjusted to fit the structure of 16S–23S rRNA internal transcribed spacers of five different Geobacillus species. Our study demonstrated the mosaic-like structure of 16S–23S rRNA internal transcribed spacers in Geobacillus. Some characteristics of these spacers of geobacilli were not previously reported for other bacteria: unusually short conserved sequence in the 5′ end region, some identical conserved blocks in both 5′ and 3′ regions of 16S–23S rRNA internal transcribed spacers, the same sequence blocks in both 16S–23S and 23S–5S rRNA intergenic spacers. Our study demonstrated quite uniform arrangement of the sequence blocks in Geobacillus thermodenitrificans. This species diverged early in the phylogenetic tree of the genus Geobacillus. For the phylogenetically recent species Geobacillus kaustophilus and Geobacillus lituanicus the low inter-and intraspecific, but high intragenomic variability, as a consequence of recent phylogenetic events, was established.

Self-sufficient cytochrome P450 monooxygenases from Bacillus thuringiensis: amplification and comparative sequence analysis@@@ Bacillus thuringiensis savarankiškosios P450 citochromo monooksigenazės geno pagausinimas ir lyginamoji sekų analizė

* Corresponding author. E-mail: donaldas.citavicius@gf.vu.lt Four primers targeting the self-sufficient cytochrome P450 monooxygenase gene in the Bacillus cereus group were designed in this study. PCR was carried out using these primers, and Bacillus thuringiensis wild type strains C32 and 1.2 as well as the reference strain HER1410 were proven to possess this gene. Our results also showed that B. thuringiensis C32 possesses two different copies of this gene. Phylogenetic analysis and comparative sequence analysis were performed in order to evaluate the differences between the sequences of B. thuringiensis C32, 1.2 and HER1410 as well as those from the public databases. The sequence of B. thuringiensis HER1410 clustered with that of B. cereus 14579T, and the sequences of B. thuringiensis C32 and 1.2 clustered with that of Bacillus weihenstephanensis KBAB4. The sequences of both B. thuringiensis Al Hakam and B. thuringiensis serovar konkukian 97–27 did not cluster with strains C32, 1.2 and HER1410. The diversity of CYP102A in B. thuringiensis strains implies that this species represents an excellent potential resource of different self-sufficient cytochrome P450 monooxygenases.