Drought-tolerant Pseudomonas sp. showed differential expression of stress-responsive genes and induced drought tolerance in Arabidopsis thaliana.

The growth and persistence of rhizobacteria in soils are highly impacted by moisture stress. In this study, we report the first transcript analysis of four Pseudomonas strains (PS1, PS2, PS3, and PS4) isolated from the root-soil interface of rice and maize associated with different moisture levels during water deprivation. Filtered Pseudomonas sp.

Heterologous Expression of Mycobacterium Alkene Monooxygenases in Gram-Positive and Gram-Negative Bacterial Hosts.

Alkene monooxygenases (MOs) are soluble di-iron-containing enzymes found in bacteria that grow on alkenes. Here, we report improved heterologous expression systems for the propene MO (PmoABCD) and ethene MO (EtnABCD) from strain NBB4. Strong functional expression of PmoABCD and EtnABCD was achieved in mc155, yielding epoxidation activities (62 and 27 nmol/min/mg protein, respectively) higher than any reported to date for heterologous expression of a di-iron MO system.

Author Correction: Seasonal total methane depletion in limestone caves.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Seasonal total methane depletion in limestone caves.

Methane concentration in caves is commonly much lower than the external atmosphere, yet the cave CH depletion causal mechanism is contested and dynamic links to external diurnal and seasonal temperature cycles unknown. Here, we report a continuous 3-year record of cave methane and other trace gases in Jenolan Caves, Australia which shows a seasonal cycle of extreme CH depletion, from ambient ~1,775 ppb to near zero during summer and to ~800 ppb in winter. Methanotrophic bacteria, some newly-discovered, rapidly consume methane on cave surfaces and in external karst soils with lifetimes in the cave of a few hours.

Insertion sequence ISPst4 activates pUC plasmid replication in Pseudomonas stutzeri.

Insertion sequences (IS) are important drivers of bacterial evolution. Here, we report a previously undescribed IS element (ISPst4) in Pseudomonas stutzeri, and its unusual interaction with plasmids introduced into this species. Transformation of the pUC19 derivative plasmid pUS23 into P.

Comparative genomics of plant-associated Pseudomonas spp.: insights into diversity and inheritance of traits involved in multitrophic interactions.

We provide here a comparative genome analysis of ten strains within the Pseudomonas fluorescens group including seven new genomic sequences. These strains exhibit a diverse spectrum of traits involved in biological control and other multitrophic interactions with plants, microbes, and insects. Multilocus sequence analysis placed the strains in three sub-clades, which was reinforced by high levels of synteny, size of core genomes, and relatedness of orthologous genes between strains within a sub-clade.

Hydrocarbon monooxygenase in Mycobacterium: recombinant expression of a member of the ammonia monooxygenase superfamily.

The copper membrane monooxygenases (CuMMOs) are an important group of enzymes in environmental science and biotechnology. Areas of relevance include the development of green chemistry for sustainable exploitation of methane (CH(4)) reserves, remediation of chlorinated hydrocarbon contamination and monitoring human impact in the biogeochemical cycles of CH(4) and nitrogen. Challenges for all these applications are that many aspects of the ecology, physiology and structure-function relationships in the CuMMOs are inadequately understood.

Untangling the multiple monooxygenases of Mycobacterium chubuense strain NBB4, a versatile hydrocarbon degrader.

Mycobacterium strain NBB4 was isolated on ethene as part of a bioprospecting study searching for novel monooxygenase (MO) enzymes of interest to biocatalysis and bioremediation. Previous work indicated that strain NBB4 contained an unprecedented diversity of MO genes, and we hypothesized that each MO type would support growth on a distinct hydrocarbon substrate. Here, we attempted to untangle the relationships between MO types and hydrocarbon substrates.

Genome Sequence of the ethene- and vinyl chloride-oxidizing actinomycete Nocardioides sp. strain JS614.

Nocardioides sp. strain JS614 grows on ethene and vinyl chloride (VC) as sole carbon and energy sources and is of interest for bioremediation and biocatalysis. Sequencing of the complete genome of JS614 provides insight into the genetic basis of alkene oxidation, supports ongoing research into the physiology and biochemistry of growth on ethene and VC, and provides biomarkers to facilitate detection of VC/ethene oxidizers in the environment.

Roles of DHA2 family transporters in drug resistance and iron homeostasis in Acinetobacter spp.

Background: Acinetobacter baumannii is a major cause of nosocomial infections worldwide due to its fitness within clinical settings and recalcitrance to conventional therapies. The drug: H(+) antiporter 2 (DHA2) family export systems encoded by A. baumannii were investigated for their roles in promoting the success ofthis organism as a human pathogen.

Unusual class 1 integron configuration found in Salmonella genomic island 2 from Salmonella enterica serovar Emek.

Salmonella genomic island 2 (SGI2) is an independently derived genomic island related to SGI1 with the integron in a different position. The integron in SGI2 was found to include an additional 2.1 kb derived from the tni module of Tn5058, Tn502, or Tn512 that was not detected previously.