Isolation and characterization of novel acetogenic strains of the genera Terrisporobacter and Acetoanaerobium.

Due to their metabolic versatility in substrate utilization, acetogenic bacteria represent industrially significant production platforms for biotechnological applications such as syngas fermentation, microbial electrosynthesis or transformation of one-carbon substrates. However, acetogenic strains from the genera Terrisporobacter and Acetoanaerobium remained poorly investigated for biotechnological applications. We report the isolation and characterization of four acetogenic Terrisporobacter strains and one Acetoanaerobium strain. All Terrisporobacter isolates showed a characteristic growth pattern under a H2 + CO2 atmosphere. An initial heterotrophic growth phase was followed by a stationary growth phase, where continuous acetate production was indicative of H2-dependent acetogenesis. One of the novel Terrisporobacter isolates obtained from compost (strain COMT) additionally produced ethanol besides acetate in the stationary growth phase in H2-supplemented cultures. Genomic and physiological characterizations showed that strain COMT represented a novel Terrisporobacter species and the name Terrisporobacter vanillatitrophus is proposed (=DSM 116160T = CCOS 2104T). Phylogenomic analysis of the novel isolates and reference strains implied the reclassification of the T. petrolearius/T. hibernicus phylogenomic cluster to the species T. petrolearius and of the A. noterae/A. sticklandii phylogenomic cluster to the species A. sticklandii. Furthermore, we provide first insights into active prophages of acetogens from the genera Terrisporobacter and Acetoanaerobium.

Comparative genome analyses of clinical and non-clinical Clostridioides difficile strains.

The pathogenic bacterium Clostridioides difficile is a worldwide health burden with increasing morbidity, mortality and antibiotic resistances. Therefore, extensive research efforts are made to unravel its virulence and dissemination. One crucial aspect for C. difficile is its mobilome, which for instance allows the spread of antibiotic resistance genes (ARG) or influence strain virulence. As a nosocomial pathogen, the majority of strains analyzed originated from clinical environments and infected individuals. Nevertheless, C. difficile can also be present in human intestines without disease development or occur in diverse environmental habitats such as puddle water and soil, from which several strains could already be isolated. We therefore performed comprehensive genome comparisons of closely related clinical and non-clinical strains to identify the effects of the clinical background. Analyses included the prediction of virulence factors, ARGs, mobile genetic elements (MGEs), and detailed examinations of the pan genome. Clinical-related trends were thereby observed. While no significant differences were identified in fundamental C. difficile virulence factors, the clinical strains carried more ARGs and MGEs, and possessed a larger accessory genome. Detailed inspection of accessory genes revealed higher abundance of genes with unknown function, transcription-associated, or recombination-related activity. Accessory genes of these functions were already highlighted in other studies in association with higher strain virulence. This specific trend might allow the strains to react more efficiently on changing environmental conditions in the human host such as emerging stress factors, and potentially increase strain survival, colonization, and strain virulence. These findings indicated an adaptation of the strains to the clinical environment. Further, implementation of the analysis results in pairwise genome comparisons revealed that the majority of these accessory genes were encoded on predicted MGEs, shedding further light on the mobile genome of C. difficile. We therefore encourage the inclusion of non-clinical strains in comparative analyses.

Novel insights into phage biology of the pathogen Clostridioides difficile based on the active virome.

The global pathogen Clostridioides difficile is a well-studied organism, and researchers work on unraveling its fundamental virulence mechanisms and biology. Prophages have been demonstrated to influence C. difficile toxin expression and contribute to the distribution of advantageous genes. All these underline the importance of prophages in C. difficile virulence. Although several C. difficile prophages were sequenced and characterized, investigations on the entire active virome of a strain are still missing. Phages were mainly isolated after mitomycin C-induction, which does not resemble a natural stressor for C. difficile. We examined active prophages from different C. difficile strains after cultivation in the absence of mitomycin C by sequencing and characterization of particle-protected DNA. Phage particles were collected after standard cultivation, or after cultivation in the presence of the secondary bile salt deoxycholate (DCA). DCA is a natural stressor for C. difficile and a potential prophage-inducing agent. We also investigated differences in prophage activity between clinical and non-clinical C. difficile strains. Our experiments demonstrated that spontaneous prophage release is common in C. difficile and that DCA presence induces prophages. Fourteen different, active phages were identified by this experimental procedure. We could not identify a definitive connection between clinical background and phage activity. However, one phage exhibited distinctively higher activity upon DCA induction in the clinical strain than in the corresponding non-clinical strain, although the phage is identical in both strains. We recorded that enveloped DNA mapped to genome regions with characteristics of mobile genetic elements other than prophages. This pointed to mechanisms of DNA mobility that are not well-studied in C. difficile so far. We also detected phage-mediated lateral transduction of bacterial DNA, which is the first described case in C. difficile. This study significantly contributes to our knowledge of prophage activity in C. difficile and reveals novel aspects of C. difficile (phage) biology.

Culture-independent detection of low-abundant Clostridioides difficile in environmental DNA via PCR.

Clostridioides difficile represents a major burden to public health. As a well-known nosocomial pathogen whose occurrence is highly associated with antibiotic treatment, most examined C. difficile strains originated from clinical specimen and were isolated under selective conditions employing antibiotics. This suggests a significant bias among analyzed C. difficile strains, which impedes a holistic view on this pathogen. In order to support extensive isolation of C. difficile strains from environmental samples, we designed a detection PCR that targets the hpdBCA-operon and thereby identifies low abundances of C. difficile in environmental samples. This operon encodes the 4-hydroxyphenylacetate decarboxylase, which catalyzes the production of the antimicrobial compound para-cresol. Amplicon-based analyses of diverse environmental samples demonstrated that the designed PCR is highly specific for C. difficile and successfully detected C. difficile despite its absence in general 16S rRNA gene-based detection strategies. Further analyses revealed the potential of the hpdBCA detection PCR sequence for initial phylogenetic classification, which allows assessment of C. difficile diversity in environmental samples via amplicon sequencing. Our findings furthermore showed that C. difficile strains isolated under antibiotic treatment from environmental samples were originally dominated by other strains according to PCR amplicon results. This provided evidence for selective cultivation of under-represented but antibiotic-resistant isolates. Thereby, we revealed a substantial bias in C. difficile isolation and research.IMPORTANCEClostridioides difficile is a main cause of diarrheic infections after antibiotic treatment with serious morbidity and mortality worldwide. Research on this pathogen and its virulence has focused on bacterial isolation from clinical specimens under antibiotic treatment, which implies a substantial bias in isolated strains. Comprehensive studies, however, require an unbiased strain collection, which is accomplished by isolation of C. difficile from diverse environmental samples and avoidance of antibiotic-based enrichment strategies. Thus, isolation can significantly benefit from our C. difficile-specific detection PCR, which rapidly verifies C. difficile presence in environmental samples and further allows estimation of the C. difficile diversity by using next-generation sequencing.

Complete genome sequence of a Clostridioides difficile cryptic C-III strain isolated from horse feces.

We provide the complete genome of a non-toxigenic Clostridioides difficile strain isolated from horse feces. The strain represents a sub-cluster in the cryptic clade C-III. The genome consists of one chromosome (4,144,784 bp) and one plasmid (10,144 bp) and encodes 3,798 putative genes.

Sexual preference for prepubescent children is associated with enhanced processing of child faces in juveniles.

Child sexual abuse offences (CSOs) represent a severe ethical and socioeconomic burden for society. Juveniles with a sexual preference for prepubescent children (PP) commit a large percentage of CSOs, but have been widely neglected in neuroscience research. Aberrant neural responses to face stimuli have been observed in men with pedophilic interest. Thus far, it is unknown whether such aberrations exist already in PP. A passive face-viewing paradigm, including the presentation of child and adult faces, was deployed and high-density electroencephalography data were recorded. The study group comprised 25 PP and the control group involved 22 juveniles with age-adequate sexual preference. Attractiveness ratings and evoked brain responses were obtained for the face stimuli. An aberrant pattern of attractiveness ratings for child vs. adult faces was found in the PP group. Moreover, elevated occipital P1 amplitudes were observed for adult vs. child faces in both groups. At longer latency (340-426 ms), a stronger negative deflection to child vs. adult faces, which was source localized in higher visual, parietal and frontal regions, was specifically observed in the PP group. Our study provides evidence for enhanced neural processing of child face stimuli in PP, which might reflect elevated attention capture of face stimuli depicting members from the sexually preferred age group. This study expands our understanding of the neural foundations underlying sexual interest in prepubescent children and provides a promising path for the uncovering of objective biomarkers of sexual responsiveness to childlike body schemes in juveniles.

Neural processing associated with cognitive empathy in pedophilia and child sexual offending.

Behavioral studies found evidence for superior cognitive empathy (CE) in pedophilic men without a history of child sexual offending (P - CSO) compared to pedophilic men with a history of child sexual offending (P + CSO). Functional magnetic resonance imaging (fMRI) studies also point to differences between P - CSO and P + CSO. Neural processing associated with CE has not yet been investigated. Therefore, the present study aimed to explore the neural correlates of CE in subjects with pedophilia with (P + CSO) and without (P - CSO) child sexual offending. 15 P + CSO, 15 P - CSO and 24 teleiophilic male controls (TC) performed a CE task during fMRI. We observed reduced activation in the left precuneus (Pcu) and increased activation in the left anterior cingulate cortex (ACC) in P - CSO compared to P + CSO. P - CSO also showed stronger connectivity between these regions, which might reflect a top-down modulation of the Pcu by the ACC toward an increased self-focused emotional reaction in social situations. There was also evidence for increased right superior temporal gyrus activation in P - CSO that might constitute a potentially compensatory recruitment due to the dampened Pcu activation. These findings provide first evidence for altered neural processing of CE in P - CSO and underline the importance of addressing CE in pedophilia and CSO in order to uncover processes relevant to effective prevention of child sexual abuse.

Characteristics of the Users of Troubled Desire, a Web-Based Self-management App for Individuals With Sexual Interest in Children: Descriptive Analysis of Self-assessment Data.

BACKGROUND: Despite the high prevalence of child sexual offenses and the increasing amounts of available child sexual abuse material, there is a global shortage of preventive interventions focusing on individuals at risk of sexual offending. The web-based app Troubled Desire aims to address this shortage by offering self-assessments and self-management training modules in different languages to individuals with sexual interests in prepubescent and early pubescent children (ie, those with pedophilic and hebephiliac sexual interest, respectively). OBJECTIVE: The aim of this study was to describe the characteristics of the users of the Troubled Desire app. METHODS: The fully completed self-assessment data gathered within the first 30 months of this study from October 25, 2017 to April 25, 2020 were investigated. The main outcome measures were (1) sociodemographic information and (2) sexual interests and sexual behaviors of the users of Troubled Desire. RESULTS: The self-assessment was completed by 4161 users. User accesses were mainly from Germany (2277/4161, 54.7%) and the United States (474/4161, 11.4%). Approximately 78.9% (3281/4161) of the users reported sexual interest in children; these users were significantly more likely to report distress and trouble owing to their sexual interest. Further, child sexual offenses and consumption of child sexual abuse material were significantly more common among users with sexual interest in children than among users with no sexual interest in children. Additionally, the majority of the offenses were not known to legal authorities. CONCLUSIONS: The Troubled Desire app is useful in reaching out to individuals with sexual interest in prepubescent and early pubescent children. However, future research is warranted to understand the prospective relevance of the Troubled Desire app in the prevention of child sexual offending.

Genome sequence analysis of the temperate bacteriophage TBP2 of the solvent producer Clostridium saccharoperbutylacetonicum N1-4 (HMT, ATCC 27021).

The genus Clostridium consists of a diverse group of pathogenic and non-pathogenic bacteria. The non-pathogenic clostridia contain several solventogenic members of industrial importance, such as Clostridium acetobutylicum or C. beijerinckii. In the process of acetone-butanol-ethanol (ABE) fermentation, these strains are used in large scale fermentation plants since almost 100 years. Soon after establishment of the first plants, the fermentation processes suffered from different bacteriophage infections worldwide. A limited set of studies addressing bacteriophages in solventogenic clostridia have been conducted since then. In this study, we present the genome sequence of the temperate bacteriophage TBP2 of the solventogenic strain C. saccharoperbutylacetonicum N1-4 (HMT) that is used for ABE fermentation. The phage genome consists of 38 039 bp and includes 48 open reading frames. Sequence analysis indicates that the genome encloses random parts of the bacterial genome in addition to its own DNA. It represents the first fully sequenced genome of a temperate bacteriophage infecting solventogenic clostridia.

Empathy in pedophilia and sexual offending against children: A multifaceted approach.

Empathy is regarded as dynamic risk factor of child sexual offending. However, empathy research in the context of child sexual abuse suffers from various problems. First, prior studies failed to differentiate between pedophilic and nonpedophilic sexual offenders. Second, there is no distinction made between cognitive and affective empathy. Third, cognitive and affective empathy toward emotional states of specific age groups (children and adults) has not been adequately addressed. The current study tackles these shortcomings investigating offending and nonoffending pedophiles and multiple aspects of empathy using self-reports and objective behavioral measures. Participants included 85 pedophilic men who committed hands-on child sexual offenses (P+CSO), 72 pedophilic men who never committed hands-on child sexual offenses (P-CSO), and 128 nonoffending teleiophilic male controls (TC). Several affective and cognitive aspects of empathy were assessed using the Multifaceted Empathy Test (MET) and the Interpersonal Reactivity Index (IRI). Whereas in self-reports (IRI) P+CSO scored lower than TC (P-CSO intermediate) in cognitive perspective-taking abilities, a performance-based measure (MET) revealed evidence for a better differentiation of emotional states in P-CSO as compared with P+CSO (TC intermediate). In addition, P+CSO and P-CSO showed significantly higher affective resonance while observing children (MET), which was paralleled by higher self-reported levels of personal distress in social situations (IRI). The results indicate evidence for higher general affective empathic resonance to children in pedophilic men but superior cognitive empathy abilities in nonoffending pedophiles only, which may act as a protective factor in the prevention of sexual offending. Together, these findings underline the importance of accounting for multiple facets of empathy when targeting pedophilia and child sexual offending. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

First Insights into the Genome Sequence of the Cellulolytic Bacterium Clostridium hungatei DSM 14427.

Clostridium hungatei is an obligate anaerobic and spore-forming bacterium, which was isolated from soil. It ferments carbohydrates, such as cellulose or d-glucose. C. hungatei is able to fix nitrogen. The draft genome consists of 1 chromosome (4.902 Mb) with 4,246 predicted protein-coding genes.