A novel phenanthrene-degrading bacterium, designated strain Sphe3 T , was isolated from a creosote-contaminated soil in Greece. Cells were non-motile, Gram-positive, aerobic, and rod-to coccus-shaped. The strain was isolated on the basis of formation of a clear zone on agar plates sprayed with phenanthrene. Optimal growth occurred at 30 6C. The G+C content of the DNA was 65.7 mol%. The polar lipid pattern of strain Sphe3 T consisted of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The dominant fatty acids were iso-C 15 : 0 , anteiso-C 15 : 0 , iso-C 16 : 0 , C 16 : 0 and anteiso-C 17 : 0 , representing .86 % of the total fatty acids. The predominant isoprenoid quinone of strain Sphe3 T was menaquinone-8 (MK-8). Based on 16S rRNA gene sequence analysis, strain Sphe3 T showed 99 and 98.9 % similarity to the type strains of Arthrobacter oxydans and Arthrobacter polychromogenes, respectively. Strain Sphe3 T showed 91 % similarity to homologues of A. oxydans and A. polychromogenes based on recA gene sequence analysis. Based on 16S rRNA and recA gene sequence analysis and DNA-DNA hybridization analysis, as well as physiological and chemotaxonomic characteristics, it is concluded that strain Sphe3 T represents a novel species of the genus Arthrobacter, for which the name Arthrobacter phenanthrenivorans sp. nov. is proposed. The type strain is Sphe3 T (5DSM 18606 T 5LMG 23796 T ).Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that are found in many polluted soils as a result of natural or industrial activities, including those of creosote wood-treatment facilities (Mueller et al., 1989). PAHs have attracted considerable attention because of their potential toxicity for higher organisms and resistance to microbial degradation (Kanaly & Harayama, 2000). A wide range of micro-organisms have been discovered that are able to degrade highly stable, toxic organic compounds such as polycyclic and aliphatic hydrocarbons (Habe & Omori, 2003;Kanaly & Harayama, 2000;Van Hamme et al., 2003). Among these micro-organisms, several Arthrobacter species are able to degrade PAHs (Grifoll et al., 1992;Seo et al., 2006). We have previously reported the phenanthrene uptake activity and membrane lipid alterations of a PAH-degrading Arthrobacter strain, Sphe3, isolated from a creosote-contaminated soil in Greece (Kallimanis et al., 2007). In the present study, on the basis of phylogenetic analysis of 16S rRNA and recA gene sequences, together with physiological and chemotaxonomic characteristics and DNA-DNA hybridization analysis, we demonstrate that strain Sphe3 represents a novel species of the genus Arthrobacter.Strain Sphe3 T was isolated from Perivleptos, a creosotepolluted site in Epirus, Greece (12 km north of the city of Ioannina), in which a wood-preserving industry had operated for over 30 years (Kallimanis et al., 2007). Soil samples (10 g) were mixed with 100 ml of minimal medium M9 (Sambrook et al., 1989) supplemented with 0.01 % (w/v) phenanthrene (in crystal form) as the sole ca...

The spontaneous alcoholic fermentation of grape must is a complex microbiological process involving a large number of various yeast species, to which the flavour of every traditional wine is largely attributed. Whilst Saccharomyces cerevisiae is primarily responsible for the conversion of sugar to alcohol, the activities of various non-Saccharomyces species enhance wine flavour. In this study, indigenous yeast strains belonging to Metschnikowia pulcherrima var. zitsae as well as Saccharomyces cerevisiae were isolated and characterized from Debina must (Zitsa, Epirus, Greece). In addition, these strains were examined for their effect on the outcome of the wine fermentation process when used sequentially as starter cultures. The resulting wine, as analyzed over three consecutive years, was observed to possess a richer, more aromatic bouquet than wine from a commercial starter culture. These results emphasize the potential of employing indigenous yeast strains for the production of traditional wines with improved flavour.

Arthrobacter phenanthrenivorans is the type species of the genus, and is able to metabolize phenanthrene as a sole source of carbon and energy. A. phenanthrenivorans is an aerobic, non-motile, and Gram-positive bacterium, exhibiting a rod-coccus growth cycle which was originally isolated from a creosote polluted site in Epirus, Greece. Here we describe the features of this organism, together with the complete genome sequence, and annotation.

Mycobacterium sp.Spyr1 is a newly isolated strain that occurs in a creosote contaminated site in Greece. It was isolated by an enrichment method using pyrene as sole carbon and energy source and is capable of degrading a wide range of PAH substrates including pyrene, fluoranthene, fluorene, anthracene and acenapthene. Here we describe the genomic features of this organism, together with the complete sequence and annotation. The genome consists of a 5,547,747 bp chromosome and two plasmids, a larger and a smaller one with sizes of 211,864 and 23,681 bp, respectively. In total, 5,588 genes were predicted and annotated.

A novel protease designated protease-A-17N-1, was purified from the halo-alkalophilic Bacillus sp. 17N-1, and found active in media containing dithiothreitol and EDTAK(2). This enzyme maintained significant activity from pH 6.00 to 9.00, showed optimum k(cat)/K(m) value at pH 7.50 and 33 degrees C. It was observed that only specific inhibitors of cysteine proteinases inhibited its activity. The pH-(k(cat)/K(m)) profile of protease-A-17N-1 was described by three pK(a)s in the acid limb, and one in the alkaline limb. Both are more likely due t3o the protonic dissociation of an acidic residue, and the development and subsequent deprotonation of an ion-pair, respectively, in its catalytic site, characteristic for cysteine proteinases. Moreover, both the obtained estimates of rate constant k(1) and the ratio k(2)/k(-1) at 25 degrees C, from the temperature-(k(cat)/K(m)) profile of protease-A-17N-1, were found similar to those estimated from the proton inventories of the same parameter, verifying the reliability of the latter methodology. Besides, the bowed-downward proton inventories of k(cat)/K(m), as well as the large inverse SIE observed for this parameter, in combination with its dependence versus temperature, were showed unambiguously that k(cat)/K(m) = k(1). Such results suggest that the novel enzyme is more likely to be a cysteine proteinase functioning via a general acid-base mechanism.

A novel halophilic bacterium, designated strain MSS4T, was isolated from the solar salterns of Mesolongi, Greece. The micro-organism, a motile, Gram-stain-positive, aerobic rod, proliferated at salinities of 1.0–4.0 M NaCl, with optimal growth at 2.5 M NaCl. Endospores were not observed. Strain MSS4T showed optimal growth at 37 °C and pH 8.0. The G+C content of its DNA was 47.2 mol%. The polar lipid pattern of strain MSS4T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidic acid and phosphatidylethanolamine. It possessed anteiso-C15 : 0, C18 : 0, C16 : 0 and anteiso-C17 : 0 as the major fatty acids (altogether representing 84.7 % of the total). The predominant isoprenoid quinone was MK-7. The cell-wall peptidoglycan contained meso-diaminopimelic acid. 16S rRNA gene sequence analysis showed that the new isolate has 96.1 % similarity to Bacillus qingdaonensis CM1T and Bacillus aidingensis 17-5T, 95.5 % to Bacillus salarius BH169T and lower similarity to other Bacillus species. These results justify the assignment of strain MSS4T to a novel species within the genus Bacillus, for which the name Bacillus halochares sp. nov. is proposed. The type strain is MSS4T (=LMG 24571T =DSM 21373T).

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Background During alcoholic fermentation, Saccharomyces cerevisiae synthesizes more than 400 different compounds with higher alcohols, acetate esters of higher alcohols and ethyl esters of medium-chain fatty acids being the most important products of its metabolism, determining the particular flavour profile of each wine. The concentration of the metabolites produced depends to a large extent on the strain used. The use of indigenous strains as starting cultures can lead to the production of wines with excellent organoleptic characteristics and distinct local character, superior in quality when compared to their commercial counterparts. However, the relationship of these wild-type genotypes, linked to specific terroirs , with the biosynthetic profiles of flavour metabolites is not completely clarified and understood. To this end, qRT-PCR was employed to examine, for the first time on the transcriptional level, the performance of an indigenous Saccharomyces cerevisiae strain (Z622) in its natural environment (Debina grape must). The expression of genes implicated in higher alcohols and esters formation was correlated with the concentrations of these compounds in the produced wine. Furthermore, by applying the same fermentation conditions, we examined the same parameters in a commercial strain (VL1) and compared its performance with the one of strain Z622. Results Strain Z622, exhibited lower concentrations of 2-methylbutanol, 3-methylbutanol and 2-phenyl ethanol, than VL1 correlating with the elevated expression levels of transaminase and decarboxylase genes. Furthermore, the significantly high induction of ADH3 throughout fermentation of Z622 probably explains the larger population numbers reached by Z622 and reflects the better adaptation of the strain to its natural environment. Regarding acetate ester biosynthesis, Z622 produced higher concentrations of total acetate esters, compared with VL1, a fact that is in full agreement with the elevated expression levels of both ATF1 and ATF2 in strain Z622. Conclusions This study provides evidence on the transcriptional level that indigenous yeast Z622 is better adapted to its natural environment able to produce wines with desirable characteristics, i.e. lower concentrations of higher alcohol and higher ester, verifying its potential as a valuable starter for the local wine-industry. Electronic supplementary material The online version of this article (10.1186/s40709-019-0096-8) contains supplementary material, which is available to authorized users.