Tertiary alcohols, such as tert-butyl alcohol (TBA) and tert-amyl alcohol (TAA) and higher homologues, are only slowly degraded microbially. The conversion of TBA seems to proceed via hydroxylation to 2-methylpropan-1,2-diol, which is further oxidized to 2-hydroxyisobutyric acid. By analogy, a branched pathway is expected for the degradation of TAA, as this molecule possesses several potential hydroxylation sites. In Aquincola tertiaricarbonis L108 and Methylibium petroleiphilum PM1, a likely candidate catalyst for hydroxylations is the putative tertiary alcohol monooxygenase MdpJ. However, by comparing metabolite accumulations in wild-type strains of L108 and PM1 and in two mdpJ knockout mutants of strain L108, we could clearly show that MdpJ is not hydroxylating TAA to diols but functions as a desaturase, resulting in the formation of the hemiterpene 2-methyl-3-buten-2-ol. The latter is further processed via the hemiterpenes prenol, prenal, and 3-methylcrotonic acid. Likewise, 3-methyl-3-pentanol is degraded via 3-methyl-1-penten-3-ol. Wild-type strain L108 and mdpJ knockout mutants formed isoamylene and isoprene from TAA and 2-methyl-3-buten-2-ol, respectively. It is likely that this dehydratase activity is catalyzed by a not-yet-characterized enzyme postulated for the isomerization of 2-methyl-3-buten-2-ol and prenol. The vitamin requirements of strain L108 growing on TAA and the occurrence of 3-methylcrotonic acid as a metabolite indicate that TAA and hemiterpene degradation are linked with the catabolic route of the amino acid leucine, including an involvement of the biotin-dependent 3-methylcrotonyl coenzyme A (3-methylcrotonyl-CoA) carboxylase LiuBD. Evolutionary aspects of favored desaturase versus hydroxylation pathways for TAA conversion and the possible role of MdpJ in the degradation of higher tertiary alcohols are discussed.

Facing increasing human demands on Earth, understanding how endangered species may survive in isolated remnants of natural habitat within heavily transformed landscapes is key to contemporary conservation biology. Against this background we here investigate the factors affecting pond occupancy in the endangered European tree frog (Hyla arborea L.) within an urban landscape, being located in north‐eastern Germany where the species is still fairly common. Our survey revealed that 58 out of 122 ponds were occupied by H. arborea. Ponds with a higher percentage of floating vegetation, being deeper and surrounded by higher percentages of crop fields and forests were more likely to be occupied, while factors associated with urbanization such as the percentage of built‐up area were strongly detrimental. Habitat requirements of H. arborea were complex as occurrence was simultaneously affected by different spatial scales, including the landscape scale, the immediate surroundings of ponds and the ponds themselves. H. arborea avoided highly urbanized areas, but occurred frequently in agricultural areas surrounding the city. The latter suggests that this species is fairly tolerant towards human‐induced transformations, and that vast arable fields yielded positive rather than negative effects on H. arborea occurrence. We conclude that the most important conservation issues for supporting H. arborea populations at the periphery of urbanized areas are (1) maintaining an open (agricultural) landscape structure, (2) providing undisturbed overwintering habitats, and (3) maintaining pond quality by halting shrub and tree encroachment.

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The skeletal parts of the metendosternite and of the anteromedian part of the abdominal venter are studied in 39 species of Chrysomelinae (representing tribes Timarchini and Chrysomelini, and 10 of the 12 subtribes of Chrysomelini) and 4 species from Galerucinae, Criocerinae, and Cassidinae. The morphology of these body parts in Chrysomelinae is compared with other cucujiform beetles based on the literature, with a focus on a tenebrionid. The morphology of the metendosternite evidently includes much homoplasy across Cucujiformia including Chrysomelidae, whereby conclusions on the polarity of characters are very limited. The (fairly poor) phylogenetic evidence from the chrysomeline metendosternite is discussed including reflection of the current classification, of the only large-scale molecular-based phylogenetic study of Chrysomelinae, and of phylogenetic evidence from glands and their secretions. Chrysomelinae consistently have a very short metendosternal stalk, the anterior tendon originates far laterally from the furcal arm, and the anterior lamina is limited to the furcal arm or entirely absent (i.e. always absent in the median part of the metendosternite). These features appear as apomorphic compared to the examined Galerucinae, Criocerinae, and Cassidinae and suggest the exclusion of Galerucinae from Chrysomelinae (contra molecularbased results). Metendosternal characters suggest Phratora to belong to Chrysomelina, and Zygogramma and Cosmogramma to be close to Chrysolinina rather than Doryphorina; both is in accord with results derived from DNA sequences and from gland secretions. The two Chrysomelinae genera with reduced hind wings (Timarcha, Crosita) show simplifications in the metendosternite. It is suggested that somecharacters may depend on the age of the adults, the development of abdominal hemi-sternites I being one such character.