Estimated Annual Healthcare Costs After Acute Pulmonary Embolism: Results From a Prospective Multicentre Cohort Study.

OBJECTIVE: Patients surviving acute pulmonary embolism (PE) necessitate long-term treatment and follow-up. However, the chronic economic impact of PE on European healthcare systems remains to be determined. METHODS AND RESULTS: We calculated the direct cost of illness during the first year after discharge for the index PE, analyzing data from a multicentre prospective cohort study in Germany. Main and accompanying readmission diagnoses were used to calculate DRG-based hospital reimbursements; anticoagulation costs were estimated from the exact treatment duration and each drug's unique national identifier; and outpatient post-PE care costs from guidelines-recommended algorithms and national reimbursement catalogues. Of 1017 patients enrolled at 17 centres, 958 (94%) completed ≥ 3-month follow-up; of those, 24% were rehospitalized (0.34 [95% CI 0.30-0.39] readmissions per PE survivor). Age, coronary artery, pulmonary and kidney disease, diabetes, and (in the sensitivity analysis of 837 patients with complete 12-month follow-up) cancer, but not recurrent PE, were independent cost predictors by hurdle gamma regression accounting for zero readmissions. Estimated rehospitalization cost was €1138 (95% CI 896-1420) per patient. Anticoagulation duration was 329 (IQR 142-365) days, with estimated average per-patient costs of €1050 (median 972; IQR 458-1197); costs of scheduled ambulatory follow-up visits amounted to €181. Total estimated direct per-patient costs during the first year after PE ranged from €2369 (primary analysis) to €2542 (sensitivity analysis). CONCLUSIONS: By estimating per-patient costs and identifying cost drivers of post-PE care, our study may inform decisions concerning implementation and reimbursement of follow-up programmes aiming at improved cardiovascular prevention. (Trial registration number: DRKS00005939).

Hypertensive Retinopathy is Not Associated with Low or High Birth Weight - Results from the Population-Based German Gutenberg Health Study.

This study investigates the association between self-reported birth weight (BW) and the prevalence of hypertensive retinopathy (HR) in a large population-based cohort in Germany, as part of the Gutenberg Health Study (GHS). The study involved analyzing fundus photographs of 6855 participants, aged 35 to 74, to assess signs of HR, classified according to the Mitchell-Wong Classification. The research aimed to explore the correlation between fetal growth restriction indicated by BW and the frequency of HR. The results showed that the frequency of HR did not significantly differ among groups with different BW ranges. In the univariable analysis, HR was initially associated with high BW, but this association disappeared after adjusting for age, sex, and cardiovascular risk factors. No association was found between low BW and HR. The study reveals novel insights as there are no prior population-based studies specifically exploring this association.

Sparse Group Penalties for bi-level variable selection.

Many data sets exhibit a natural group structure due to contextual similarities or high correlations of variables, such as lipid markers that are interrelated based on biochemical principles. Knowledge of such groupings can be used through bi-level selection methods to identify relevant feature groups and highlight their predictive members. One of the best known approaches of this kind combines the classical Least Absolute Shrinkage and Selection Operator (LASSO) with the Group LASSO, resulting in the Sparse Group LASSO. We propose the Sparse Group Penalty (SGP) framework, which allows for a flexible combination of different SGL-style shrinkage conditions. Analogous to SGL, we investigated the combination of the Smoothly Clipped Absolute Deviation (SCAD), the Minimax Concave Penalty (MCP) and the Exponential Penalty (EP) with their group versions, resulting in the Sparse Group SCAD, the Sparse Group MCP, and the novel Sparse Group EP (SGE). Those shrinkage operators provide refined control of the effect of group formation on the selection process through a tuning parameter. In simulation studies, SGPs were compared with other bi-level selection methods (Group Bridge, composite MCP, and Group Exponential LASSO) for variable and group selection evaluated with the Matthews correlation coefficient. We demonstrated the advantages of the new SGE in identifying parsimonious models, but also identified scenarios that highlight the limitations of the approach. The performance of the techniques was further investigated in a real-world use case for the selection of regulated lipids in a randomized clinical trial.

Obesity-related inflammatory protein signature in cardiovascular clinical outcomes: results from the Gutenberg Health Study.

OBJECTIVE: The objective of this study was to investigate whether an obesity-related inflammatory protein signature (OIPS) is associated with adverse cardiovascular events. METHODS: The Olink Target 96 Inflammation panel was performed in 6662 participants from the population-based Gutenberg Health Study (GHS). The OIPS was selected by a logistic regression model, and its association with cardiovascular outcomes was evaluated by Cox regression analysis. The GHS-derived OIPS was externally validated in the MyoVasc study. RESULTS: The identified OIPS entailed 21 proteins involved in chemokine activity, tumor necrosis factor (TNF) receptor binding, and growth factor receptor binding. The signature revealed a novel positive association of axis inhibition protein 1 with obesity. The OIPS was associated with increased risk of all-cause and cardiac deaths, major adverse cardiovascular events, and incident coronary artery disease, independent of clinical covariates and established risk instruments. A BMI-stratified analysis confirmed the association of OIPS with increased death in those with obesity and overweight and with increased risk for coronary artery disease in those with obesity. The association of OIPS with increased risk of all-cause and cardiac deaths was validated in the MyoVasc cohort. CONCLUSIONS: The OIPS showed a significant association with adverse clinical outcomes, particularly in those with overweight and obesity, and represents a promising tool for identifying patients at higher risk for worse cardiovascular outcomes.

Noise annoyance due to different sources is associated with tinnitus presence and distress in the general population.

BACKGROUND: The pathophysiology of tinnitus is not yet fully understood. Although there is a large amount of evidence associating traffic noise exposure with non-auditory health outcomes, there is no evidence regarding the impact of noise annoyance on auditory disorders such as tinnitus. OBJECTIVE: Thus, we aimed to investigate the association between noise annoyance due to different sources and tinnitus presence and distress in the general population. METHODS: Data of 6813 participants from a large German population-based cohort were used (Gutenberg Health Study). Participants were asked about the presence of tinnitus and how much they were bothered by it. In addition, information on annoyance from road traffic, aircraft, railways, industrial, and neighborhood noise during the day and sleep was collected through validated questionnaires. RESULTS: The prevalence of tinnitus was 27.3%, and the predominant sources of noise annoyance in these subjects were aircraft, neighborhood, and road traffic noise. Overall, logistic regression results demonstrated consistent positive associations between annoyance due to different noise sources and prevalent risk of tinnitus with increases in odds ratios ranging from 4 to 11% after adjustment for sex, age, and socioeconomic status. Likewise, consistent increases in odds ratios were observed for tinnitus distress in subjects with prevalent tinnitus. For instance, neighborhood noise annoyance during the sleep was associated with a 26% increase in tinnitus distress (OR 1.26, 95% CI 1.13; 1.39). IMPACT: This is the first study investigating the association between noise annoyance and tinnitus presence and distress in a large cohort of the general population. Our results indicate consistent and positive associations between various sources of noise annoyance and tinnitus. These unprecedented findings are highly relevant as noise annoyance and tinnitus are widespread. The precise etiology and locus of tinnitus remain unknown, but excessive noise exposure is thought to be among the major causes. This study suggests that transportation and neighborhood noise levels thought merely to contribute to annoyance and non-auditory health effects may be sufficient to cause or exacerbate tinnitus.

Role of inflammatory signaling pathways involving the CD40-CD40L-TRAF cascade in diabetes and hypertension-insights from animal and human studies.

CD40L-CD40-TRAF signaling plays a role in atherosclerosis progression and affects the pathogenesis of coronary heart disease (CHD). We tested the hypothesis that CD40L-CD40-TRAF signaling is a potential therapeutic target in hyperlipidemia, diabetes, and hypertension. In mouse models of hyperlipidemia plus diabetes (db/db mice) or hypertension (1 mg/kg/d angiotensin-II for 7 days), TRAF6 inhibitor treatment (2.5 mg/kg/d for 7 or 14 days) normalized markers of oxidative stress and inflammation. As diabetes and hypertension are important comorbidities aggravating CHD, we explored whether the CD40L-CD40-TRAF signaling cascade and their associated inflammatory pathways are expressed in CHD patients suffering from comorbidities. Therefore, we analyzed vascular bypass material (aorta or internal mammary artery) and plasma from patients with CHD with diabetes and/or hypertension. Our Olink targeted plasma proteomic analysis using the IMMUNO-ONCOLOGY panel revealed a pattern of step-wise increase for 13/92 markers of low-grade inflammation with significant changes. CD40L or CD40 significantly correlated with 38 or 56 other inflammatory targets. In addition, specific gene clusters that correlate with the comorbidities were identified in isolated aortic mRNA of CHD patients through RNA-sequencing. These signaling clusters comprised CD40L-CD40-TRAF, immune system, hemostasis, muscle contraction, metabolism of lipids, developmental biology, and apoptosis. Finally, immunological analysis revealed key markers correlated with comorbidities in CHD patients, such as CD40L, NOX2, CD68, and 3-nitrotyrosine. These data indicate that comorbidities increase inflammatory pathways in CHD, and targeting these pathways will be beneficial in reducing cardiovascular events in CHD patients with comorbidities.

Matrix metalloproteinase 9 (MMP-9) activity, hippocampal extracellular free water, and cognitive deficits are associated with each other in early phase psychosis.

Increasing evidence points toward the role of the extracellular matrix, specifically matrix metalloproteinase 9 (MMP-9), in the pathophysiology of psychosis. MMP-9 is a critical regulator of the crosstalk between peripheral and central inflammation, extracellular matrix remodeling, hippocampal development, synaptic pruning, and neuroplasticity. Here, we aim to characterize the relationship between plasma MMP-9 activity, hippocampal microstructure, and cognition in healthy individuals and individuals with early phase psychosis. We collected clinical, blood, and structural and diffusion-weighted magnetic resonance imaging data from 39 individuals with early phase psychosis and 44 age and sex-matched healthy individuals. We measured MMP-9 plasma activity, hippocampal extracellular free water (FW) levels, and hippocampal volumes. We used regression analyses to compare MMP-9 activity, hippocampal FW, and volumes between groups. We then examined associations between MMP-9 activity, FW levels, hippocampal volumes, and cognitive performance assessed with the MATRICS battery. All analyses were controlled for age, sex, body mass index, cigarette smoking, and years of education. Individuals with early phase psychosis demonstrated higher MMP-9 activity (p < 0.0002), higher left (p < 0.05) and right (p < 0.05) hippocampal FW levels, and lower left (p < 0.05) and right (p < 0.05) hippocampal volume than healthy individuals. MMP-9 activity correlated positively with hippocampal FW levels (all participants and individuals with early phase psychosis) and negatively with hippocampal volumes (all participants and healthy individuals). Higher MMP-9 activity and higher hippocampal FW levels were associated with slower processing speed and worse working memory performance in all participants. Our findings show an association between MMP-9 activity and hippocampal microstructural alterations in psychosis and an association between MMP-9 activity and cognitive performance. Further, more extensive longitudinal studies should examine the therapeutic potential of MMP-9 modulators in psychosis.

Impact of depersonalization on the course of depression: longitudinal observations from the gutenberg health study.

BACKGROUND: Symptoms of depersonalization (DP) and derealization (DR) are a risk factor for more severe impairment, non-response to various treatments, and a chronic course. In this study, we investigated the effects of DP/DR symptoms in patients with clinically significant depressive symptoms on clinical characteristics and various outcomes in a representative population-based sample with a 5-year follow-up. METHODS: The middle-aged sample comprised n = 10,422 persons at baseline, of whom n = 9,301 were free from depressive and DP/DR symptoms. N = 522 persons had clinically significant depression (PHQ-9 ≥ 10) and co-occurring DP/DR symptoms, and n = 599 persons had clinically significant depression (PHQ-9 ≥ 10) without DP/DR symptoms. RESULTS: There were substantial health disparities between persons with and without depression. These disparities concerned a wide range of life domains, including lower quality of the recalled early life experiences with the parents, current socioeconomic status, social integration (partnership, loneliness), current social and interpersonal stressors (family, work), functional bodily complaints (e.g., tinnitus, migraine, chest pain), unhealthy lifestyle, and the prevalence of already developed physical diseases. These disparities persisted to the 5-year follow-up and were exceptionally severe for depressed persons with co-occurring DP/DR symptoms. Among the depressed persons, the co-occurrence of DP/DR symptoms more than doubled the risk for recurrence or persistence of depression. Only 6.9% of depressed persons with DP/DR symptoms achieved remission at the 5-year follow-up (PHQ-9 < 5). Depression with and without co-occurring DP/DR worsened self-rated physical health significantly. The impact of depression with co-occurring DP/DR on the worsening of the self-rated physical health status was stronger than those of age and major medical diseases (e.g., heart failure). However, only depression without DP/DR was associated with mortality in a hazard regression analysis adjusted for age, sex, and lifestyle. CONCLUSIONS: The results demonstrated that DP/DR symptoms represent an important and easily assessable prognostic factor for the course of depression and health outcomes. Given the low remission rates for depression in general and depression with DP/DR in particular, efforts should be made to identify and better support this group, which is disadvantaged in many aspects of life.

Interpretability of bi-level variable selection methods.

Variable selection is usually performed to increase interpretability, as sparser models are easier to understand than full models. However, a focus on sparsity is not always suitable, for example, when features are related due to contextual similarities or high correlations. Here, it may be more appropriate to identify groups and their predictive members, a task that can be accomplished with bi-level selection procedures. To investigate whether such techniques lead to increased interpretability, group exponential LASSO (GEL), sparse group LASSO (SGL), composite minimax concave penalty (cMCP), and least absolute shrinkage, and selection operator (LASSO) as reference methods were used to select predictors in time-to-event, regression, and classification tasks in bootstrap samples from a cohort of 1001 patients. Different groupings based on prior knowledge, correlation structure, and random assignment were compared in terms of selection relevance, group consistency, and collinearity tolerance. The results show that bi-level selection methods are superior to LASSO in all criteria. The cMCP demonstrated superiority in selection relevance, while SGL was convincing in group consistency. An all-round capacity was achieved by GEL: the approach jointly selected correlated and content-related predictors while maintaining high selection relevance. This method seems recommendable when variables are grouped, and interpretation is of primary interest.

Colabind: A Cloud-Based Approach for Prediction of Binding Sites Using Coarse-Grained Simulations with Molecular Probes.

Binding site prediction is a crucial step in understanding protein-ligand and protein-protein interactions (PPIs) with broad implications in drug discovery and bioinformatics. This study introduces Colabind, a robust, versatile, and user-friendly cloud-based approach that employs coarse-grained molecular dynamics simulations in the presence of molecular probes, mimicking fragments of drug-like compounds. Our method has demonstrated high effectiveness when validated across a diverse range of biological targets spanning various protein classes, successfully identifying orthosteric binding sites, as well as known druggable allosteric or PPI sites, in both experimentally determined and AI-predicted protein structures, consistently placing them among the top-ranked sites. Furthermore, we suggest that careful inspection of the identified regions with a high affinity for specific probes can provide valuable insights for the development of pharmacophore hypotheses. The approach is available at https://github.com/porekhov/CG_probeMD.

Current and past depression as risk factors for incident type 2 diabetes mellitus and pre-diabetes in men and women: evidence from a longitudinal community cohort.

BACKGROUND: Depression is associated with an increased risk for type 2 diabetes mellitus. However, depression may take different courses, and it is not fully understood how these affect the development of diabetes. It is further to be determined whether sex modifies the association between depression and type 2 diabetes. METHODS: We analyzed data from the Gutenberg Health Study, a longitudinal and population-based cohort study (N = 15,010) in Germany. Depressive symptoms (measured by PHQ-9), history of depression, diabetes mellitus, and relevant covariates were assessed at baseline, and the outcomes of prediabetes and type 2 diabetes mellitus were evaluated 5 years later. Logistic regression was used to estimate odds ratios of incident prediabetes and type 2 diabetes mellitus, adjusting for potential confounders as identified in a Directed Acyclic Graph. RESULTS: In the confounder adjusted model, current depression (PHQ-9 ≥ 10 at baseline; OR = 1.79, 95% CI = 1.11 to 2.74, p = 0.011), and persistent depression had a statistically significant (OR = 2.44, 95% CI = 1.62 to 3.54, p = 0.005) effect on incident type 2 diabetes mellitus. A history of depression without current depression had no statistically significant effect on type 2 diabetes (OR = 1.00, 95% CI = 0.68 to 1.43, p = 0.999). The effect of depression on incident diabetes did not differ significantly between women (OR = 2.02; 95% CI = 1.32 to 3.09) and men (OR = 2.16; 95% CI = 1.41 to 3.31; p-value for interaction on the multiplicative scale p = 0.832 and on the additive scale p = 0.149). Depression did not have a significant effect on incident prediabetes. CONCLUSION: This study shows how the history and trajectory of depression shape the risk for diabetes. This raises interesting questions on the cumulative effects of depression trajectories on diabetes and body metabolism in general. Depression can negatively affect physical health, contributing to increased morbidity and mortality in people with mental disorders.

Change of Intraocular Pressure Over 5 Years and its Relationship to Cardiovascular Parameters: Results From the Gutenberg Health Study.

Purpose: To investigate the longitudinal change in intraocular pressure (IOP) over 5 years and its relationship with cardiovascular parameters in a population-based sample in Germany. Methods: The Gutenberg Health Study is a prospective, observational, single-center cohort study. The sample was equally stratified for sex, residence, and age decade. IOP was measured with noncontact tonometry at baseline and at 5-year follow-up. Cardiovascular parameters, including body mass index (BMI), systolic blood pressure, and diabetes status, were assessed. Participants without IOP measurement at one time point, who were taking IOP-lowering medications, or who had ophthalmic surgery during the 5-year follow-up interval were excluded, as well as those with glaucoma diagnosis. Univariable and multivariable linear regression analyses were conducted. Results: This analysis included 9633 participants (48.9% female). The mean IOP increased from 14.04 ± 2.78 mmHg at baseline to 14.77 ± 2.92 mmHg at 5-year follow-up (P < 0.001). In multivariable linear regression analyses, an increase in BMI was associated with an increase in IOP over time (P < 0.001), whereas a higher baseline BMI was associated with a lower IOP change (P < 0.001). Higher age and male sex were associated with higher IOP change (P < 0.001). A change in systolic blood pressure was associated with IOP change, whereas baseline systolic blood pressure and diabetes status were not associated. Conclusions: This population-based study found a relationship between IOP change over 5 years and BMI and systolic blood pressure change, respectively. These findings suggest the importance of monitoring cardiovascular risk factors in IOP management.

Feasibility and efficacy of a novel size adjustable cryoballoon for ablation of atrial fibrillation.

The aim of the present case series was to characterize the feasibility of a novel size adjustable cryoballoon system (PolarX Fit, Boston Scientific, Marlborough, MA, USA). This cryoballoon catheter can be inflated to two different diameters (28 mm and 31 mm) within the same procedure allowing vein adapted PVI. In summary, the novel size adjustable cryoballoon shows similar characteristics as the established versions. The intraprocedural flexibility of balloon size led to employment of the larger variant in the majority of freeze applications. Of note, in all but one procedure, both sizes were employed to ensure optimal occlusion for all veins. This initial series suggests that the size adjustable balloon offers more flexibility of obtain optimal occlusions in particular, in challenging anatomies, including common pulmonary vein ostia.

Prevalence of Overweight and Obesity, Its Complications, and Progression in a 10-Year Follow-Up in the Gutenberg Health Study (GHS).

INTRODUCTION: Overweight and obesity lead to numerous complications and their treatment. The associated costs represent a health and sociopolitical burden. Therefore, the development of overweight and obesity is of great importance for health policy. METHODS: The Gutenberg Health Study (GHS), a population-based observational study of individuals aged 35-74 years in the city of Mainz and the district of Mainz-Bingen, examined current data on the prevalence and development of overweight and obesity and their association with concomitant diseases and medication use. RESULTS: Among men, 48.1% were overweight and 26.3% had obesity. Among women, these proportions were 32.1% and 24.1%, respectively. Elevated body mass index (BMI) was associated with numerous complications, particularly insulin resistance and type 2 diabetes, arterial hypertension, elevated triglycerides and low HDL cholesterol, and cardiovascular disease. Accordingly, medications to treat these conditions were used significantly more often in individuals with elevated BMI. During the 10-year observation period, mean weight increased in the population. Both men and women had a moderate but significant increase in BMI compared to men and women of the same age at baseline. Individual weight changes over the 10-year observation period, on the other hand, were age-dependent. In the two younger age decades, weight gain was observed, while in the oldest age decade, mean body weight decreased. CONCLUSION: These current data confirm that overweight and obesity are associated with relevant complications and that these complications lead to significant use of appropriate medications. The study also suggests that there is a significant trend toward increased prevalence of obesity (BMI ≥30) over the 10-year period.

Cumulative social disadvantage and cardiovascular disease burden and mortality.

AIMS: To investigate the association between cumulative social disadvantage and cardiovascular burden and mortality in a large cohort of the general population. METHODS AND RESULTS: Cross-sectional (n = 15 010, aged 35 to 74 years, baseline investigation period 2007 to 2012) and longitudinal data (5- and 10-year follow-ups from 2012 to 2022) from the Gutenberg Health Study were used to investigate the association between individual socioeconomic status (SES, measured via a validated questionnaire) and cardiovascular disease (CVD, composite of atrial fibrillation, coronary artery disease, myocardial infarction, stroke, chronic heart failure, peripheral artery disease, and/or venous thromboembolism) risk and mortality. Subjects with prevalent CVD had a lower SES sum score, as well as lower education, occupation, and household net-income scores (all P < 0.0001). Logistic regression analysis showed that a low SES (vs. high, defined by validated cut-offs) was associated with 19% higher odds of prevalent CVD [odds ratio (OR) 1.19, 95% CI 1.01; 1.40] in the fully adjusted model. At 5-year follow-up, low SES was associated with both increased cardiovascular [hazard ratio (HR) 5.36, 2.24; 12.82] and all-cause mortality (HR 2.23, 1.51; 3.31). At 10-year follow-up, low SES was associated with a 68% higher risk of incident CVD (OR 1.68, 1.12; 2.47) as well as 86% higher all-cause mortality (HR 1.86, 1.55; 2.24). In general, the education and occupation scores were stronger related to risk of CVD and death than the household net-income score. Low SES was estimated to account for 451.45 disability-adjusted life years per 1000 people (years lived with disability 373.41/1000 and years of life lost 78.03/1000) and an incidence rate of 11 CVD cases and 3.47 CVD deaths per 1000 people per year. The population attributable fraction for CVD incidence after 5 years was 4% due to low SES. CONCLUSION: Despite universal healthcare access, cumulative social disadvantage remains associated with higher risk of CVD and mortality. Dimensions of education and occupation, but not household net income, are associated with outcomes of interest.

Low socioeconomic status is associated with higher risk of incident cardiovascular disease (CVD) and mortality in a large cohort of the general population even after comprehensive adjustment for associated variables. Education and occupation may be more important regarding CVD and mortality risk as compared to the household net income. From a public health perspective, policies should strengthen efforts to reduce socioeconomic inequalities by ensuring equal access to education and employment.

Age standardization and time-of-day performance for the Oldenburg Sentence Test (OLSA): results from the population-based Gutenberg Health Study.

PURPOSE: The Oldenburg Sentence Test (OLSA) is a German matrix test designed to determine speech recognition thresholds (SRT). It is widely used for hearing-aids and cochlear implant fitting, but an age-adjusted standard is still lacking. In addition, knowing that the ability to concentrate is an important factor in OLSA performance, we hypothesized that OLSA performance would depend on the time of day it was administered. The aim of this study was to propose an age standardization for the OLSA and to determine its diurnal performance. METHODS: The Gutenberg Health Study is an ongoing population-based study and designed as a single-centre observational, prospective cohort study. Participants were interviewed about common otologic symptoms and tested with pure-tone audiometry and OLSA. Two groups-subjects with and without hearing loss-were established. The OLSA was performed in two runs. The SRT was evaluated for each participant. Results were characterized by age in 5-year cohorts, gender and speech recognition threshold (SRT). A time stamp with an hourly interval was also implemented. RESULTS: The mean OLSA SRT was - 6.9 ± 1.0 dB (group 1 male) and - 7.1 ± 0.8 dB (group 1 female) showing an inverse relationship with age in the whole cohort, whereas a linear increase was observed in those without hearing loss. OLSA-SRT values increased more in males than in females with increasing age. No statistical significance was found for the diurnal performance. CONCLUSIONS: A study with 2900 evaluable Oldenburg Sentence Tests is a novelty and representative for the population of Mainz and its surroundings. We postulate an age- and gender-standardized scale for the evaluation of the OLSA. In fact, with an intergroup standard deviation (of about 1.5 dB) compared to the age dependence of 0.7 dB/10 years, this age normalization should be considered as clinically relevant.

Nearly complete structure of bacteriophage DT57C reveals architecture of head-to-tail interface and lateral tail fibers.

The T5 family of viruses are tailed bacteriophages characterized by a long non-contractile tail. The bacteriophage DT57C is closely related to the paradigmal T5 phage, though it recognizes a different receptor (BtuB) and features highly divergent lateral tail fibers (LTF). Considerable portions of T5-like phages remain structurally uncharacterized. Here, we present the structure of DT57C determined by cryo-EM, and an atomic model of the virus, which was further explored using all-atom molecular dynamics simulations. The structure revealed a unique way of LTF attachment assisted by a dodecameric collar protein LtfC, and an unusual composition of the phage neck constructed of three protein rings. The tape measure protein (TMP) is organized within the tail tube in a three-stranded parallel α-helical coiled coil which makes direct contact with the genomic DNA. The presence of the C-terminal fragment of the TMP that remains within the tail tip suggests that the tail tip complex returns to its original state after DNA ejection. Our results provide a complete atomic structure of a T5-like phage, provide insights into the process of DNA ejection as well as a structural basis for the design of engineered phages and future mechanistic studies.