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The northern bat (Eptesicus nilssonii) is the most northern bat species in the world. Its distribution covers whole Eurasia, and the species is thus well adapted to different habitat types. However, recent population declines have been reported and rapid conservation efforts are needed. Here we present a high-quality de novo genome assembly of a female northern bat from Finland (BLF_Eptnil_asm_v1.0). The assembly was generated using a combination of Pacbio and Omni-C technologies. The primary assembly comprises 726 scaffolds spanning 2.0 Gb, represented by a scaffold N50 of 102 Mb, a contig N50 of 66.2 Mb, and a BUSCO completeness score of 93.73%. Annotation of the assembly identified 20,250 genes. This genome will be an important resource for the conservation and evolutionary genomic studies especially in understanding how rapid environmental changes affect northern species. [ABSTRACT FROM AUTHOR]

The 1,100 species of bats (1) constitute ≅ 20% of known mammalian species and are outnumbered only by animals in the order Rodentia. Bats play a vital role in natural [...]

Transposon mutagenesis is a powerful technique for generating collections of insertion mutants for genetic studies. This paper describes how phage Mu DNA transposition complexes, transpososomes, can be exploited for gene delivery to efficiently introduce selectable markers to genomes of Gram-positive bacteria. Mu transpososomes were assembled in vitro with custom-designed mini-Mu transposons, concentrated, and electroporated into cells of three Gram-positive bacterial species: Staphylococcus aureus, Streptococcus pyogenes and Streptococcus suis. Within cells, the complexes reproduced an authentic DNA transposition reaction and integrated the delivered transposons into the bacterial genomes, yielding single-copy insertions. The integration efficiency among different species and strains of Gram-positive bacteria ranged from 1 x [10.sup.1] to 2 x [10.sup.4] c.f.u. [([micro]g introduced transposon DNA). sup.-1]. The strategy should be applicable to a variety of other Gram-positive species after initial optimization of certain key factors affecting transposon delivery, such as the preparation method of competent cells and physical parameters of electroporation. This study extends the scope of the Mu transpososome delivery-based genomic DNA integration strategy to Gram-positive bacteria. Thus, a straightforward generation of sizeable mutant banks is feasible for these bacteria, potentiating several types of genomic-level approaches for studies of a variety of important bacterial processes, such as pathogenicity.

Candidatus Bartonella mayotimonensis was detected in 2010 from an aortic valve sample of a patient with endocarditis from Iowa, the United States of America. The environmental source of the potentially new endocarditis-causing Bartonella remained elusive. We set out to study the prevalence and diversity of bat-associated Bartonella in North America. During 2015, mist nets and harp traps were used to capture 92 bats belonging to two species: little brown myotis ( Myotis lucifugus Le Conte 1831, n = 73) and the gray myotis ( M. grisescens A.H. Howell 1909, n = 19) in Kentucky, Michigan, Pennsylvania, and Tennessee. DNA preparations of peripheral blood samples from bats were subjected to a three-marker ( gltA, rpoB, and intergenic spacer region [ISR]) multilocus sequence analysis. Sequence-verified gltA-positive PCR amplicons were obtained from nine samples. Three sequences were 99.7-100% identical with the gltA sequence of the Iowa endocarditis patient strain. Analysis of rpoB and ISR sequences demonstrated that one little brown myotis sample from the Upper Peninsula of Michigan contained Bartonella DNA, with 100% sequence identity with the Iowa endocarditis patient strain DNA. It appears possible that bats are a reservoir of Candidatus Bartonella mayotimonensis in North America. [ABSTRACT FROM AUTHOR]

Bartonella spp. are facultative intracellular bacteria that typically cause a long-lasting intraerythrocytic bacteremia in their mammalian reservoir hosts, thereby favoring transmission by blood-sucking arthropods. In most cases, natural reservoir host infections are subclinical and the relapsing intraerythrocytic bacteremia may last weeks, months, or even years. In this review, we will follow the infection cycle of Bartonella spp. in a reservoir host, which typically starts with an intradermal inoculation of bacteria that are superficially scratched into the skin from arthropod feces and terminates with the pathogen exit by the blood-sucking arthropod. The current knowledge of bacterial countermeasures against mammalian immune response will be presented for each critical step of the pathogenesis. The prevailing models of the still-enigmatic primary niche and the anatomical location where bacteria reside, persist, and are periodically seeded into the bloodstream to cause the typical relapsing Bartonella spp. bacteremia will also be critically discussed. The review will end up with a discussion of the ability of Bartonella spp., namely Bartonella henselae, Bartonella quintana, and Bartonella bacilliformis, to induce tumor-like vascular deformations in humans having compromised immune response such as in patients with AIDS. [ABSTRACT FROM AUTHOR]

Bordetella pertussis is the causative agent of whooping cough, a highly contagious respiratory disease. Pertussis toxin (PT), a major virulence factor secreted by B. pertussis, is an AB5-type protein complex topologically related to cholera toxin. The PT protein complex is internalized by host cells and follows a retrograde trafficking route to the endoplasmic reticulum, where it subsequently dissociates. The released enzymatic S1 subunit is then translocated from the endoplasmic reticulum into the cytosol and subsequently ADP-ribosylates the inhibitory alpha-subunits (Gαi) of heterotrimeric G proteins, thus promoting dysregulation of G protein-coupled receptor signaling. However, the mechanistic details of the ADP-ribosylation activity of PT are not well understood. Here, we describe crystal structures of the S1 subunit in complex with nicotinamide adenine dinucleotide (NAD+), with NAD+ hydrolysis products ADP-ribose and nicotinamide, with NAD+ analog PJ34, and with a novel NAD+ analog formed upon S1 subunit crystallization with 3-amino benzamide and NAD+, which we name benzamide amino adenine dinucleotide. These crystal structures provide unprecedented insights into pre- and post-NAD+ hydrolysis steps of the ADP-ribosyltransferase activity of PT. We propose that these data may aid in rational drug design approaches and further development of PT-specific small-molecule inhibitors. [ABSTRACT FROM AUTHOR]

Bordetella pertussis is the causative agent of whooping cough, a highly contagious respiratory disease. Pertussis toxin (PT), a major virulence factor secreted by B. pertussis, is an AB5-type protein complex topologically related to cholera toxin. The PT protein complex is internalized by host cells and follows a retrograde trafficking route to the endoplasmic reticulum, where it subsequently dissociates. The released enzymatic S1 subunit is then translocated from the endoplasmic reticulum into the cytosol and subsequently ADP-ribosylates the inhibitory alpha-subunits (Gαi) of heterotrimeric G proteins, thus promoting dysregulation of G protein-coupled receptor signaling. However, the mechanistic details of the ADP-ribosylation activity of PT are not well understood. Here, we describe crystal structures of the S1 subunit in complex with nicotinamide adenine dinucleotide (NAD+), with NAD+ hydrolysis products ADP-ribose and nicotinamide, with NAD+ analog PJ34, and with a novel NAD+ analog formed upon S1 subunit crystallization with 3-amino benzamide and NAD+, which we name benzamide amino adenine dinucleotide. These crystal structures provide unprecedented insights into pre- and post-NAD+ hydrolysis steps of the ADP-ribosyltransferase activity of PT. We propose that these data may aid in rational drug design approaches and further development of PT-specific small-molecule inhibitors., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Candidatus Bartonella mayotimonensis was detected in 2010 from an aortic valve sample of a patient with endocarditis from Iowa, the United States of America. The environmental source of the potentially new endocarditis-causing Bartonella remained elusive. We set out to study the prevalence and diversity of bat-associated Bartonella in North America. During 2015, mist nets and harp traps were used to capture 92 bats belonging to two species: little brown myotis (Myotis lucifugus Le Conte 1831, n = 73) and the gray myotis (M. grisescens A.H. Howell 1909, n = 19) in Kentucky, Michigan, Pennsylvania, and Tennessee. DNA preparations of peripheral blood samples from bats were subjected to a three-marker (gltA, rpoB, and intergenic spacer region [ISR]) multilocus sequence analysis. Sequence-verified gltA-positive PCR amplicons were obtained from nine samples. Three sequences were 99.7-100% identical with the gltA sequence of the Iowa endocarditis patient strain. Analysis of rpoB and ISR sequences demonstrated that one little brown myotis sample from the Upper Peninsula of Michigan contained Bartonella DNA, with 100% sequence identity with the Iowa endocarditis patient strain DNA. It appears possible that bats are a reservoir of Candidatus Bartonella mayotimonensis in North America.

Although bats have been implicated as reservoir hosts for a number of zoonotic and life-threatening viruses, the bat bacterial flora and its zoonotic threat remain elusive. However, members of the vector-borne bacterial genera Bartonella causing various human as well as animal diseases have recently been isolated or detected from bats and their ectoparasites. In this study, we sampled 124 insectivorous microbats (Daubenton's bat, Myotis daubentonii) for peripheral blood in southwestern Finland in 2010. A Bartonella-specific PCR targeting rpoB (RNA polymerase β-subunit) was positive with blood samples from 46 bats (prevalence 37%). Scaled mass indexes of the infected and noninfected bats did not differ (p = 0.057). One rpoB sequence was identical with the rpoB sequence of B. naantaliensis strain 2574/1, previously isolated from bats in Finland. The rest of the sequences were highly similar to each other with nucleotide identity scores of 96% or higher. Nucleotide identity scores to the previously described type strain sequences of Bartonella or other database entries were no higher than 87%. Sequence analyses of another gene, gltA (citrate synthase), gave no higher than 90% nucleotide identity scores. On the basis of the conventional 95% sequence similarity cutoff in bacterial species delineation, a novel species of Bartonella was detected. We propose a species name Candidatus B. hemsundetiensis. Phylogenetic analyses based on rpoB and gltA sequences indicate that Candidatus B. hemsundetiensis clusters in a deep-branching position close to the ancestral species B. tamiae and B. bacilliformis. Our study reinforces the importance of bats as reservoirs of Bartonella.