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This book brings the emergent interest in social class and inequality to the field of television studies. It reveals how the new visibility of class matters in serial television functions aesthetically and examines the cultural class politics articulated in these programmes. This ground-breaking volume argues that reality and quality TV's intricate politics of class entices viewers not only to grapple with previously invisible socio-economic realities but also to reconsider their class alignment. The stereotypical ways of framing class are now supplemented by those dedicated to exposing the economic and socio-psychological burdens of the (lower) middle class. The case studies in this book demonstrate how sophisticated narrative techniques coincide with equally complex ways of exposing class divisions in contemporary American life and how the examined shows disrupt the hegemonic order of class. The volume therefore also invites a rethinking of conventional models of social stratification.

Nearly all bacteria are encased in a peptidoglycan cell wall, an essential polysaccharide structure that protects the cell from osmotic rupture and reinforces cell shape. The integrity of this protective barrier must be maintained across the diversity of environmental conditions wherein bacteria replicate. However, at the cell surface, the cell wall and its synthesis machinery face unique challenges that threaten their integrity. Directly exposed to the extracellular environment, the peptidoglycan synthesis machinery encounters dynamic and extreme physicochemical conditions, which may impair enzymatic activity and critical protein-protein interactions. Biotic and abiotic stressors—including host defenses, cell wall active antibiotics, and predatory bacteria and phage—also jeopardize peptidoglycan integrity by introducing lesions, which must be rapidly repaired to prevent cell lysis. Here, we review recently discovered mechanisms that promote robust peptidoglycan synthesis during environmental and acute stress and highlight the opportunities and challenges for the development of cell wall active therapeutics. Single-celled organisms must adapt their physiology to persist and propagate across a wide range of environmental conditions. The growth and division of bacterial cells depend on continuous synthesis of an essential extracellular barrier: the peptidoglycan cell wall, a polysaccharide matrix that counteracts turgor pressure and confers cell shape. Unlike many other essential processes and structures within the bacterial cell, the peptidoglycan cell wall and its synthesis machinery reside at the cell surface and are thus uniquely vulnerable to the physicochemical environment and exogenous threats. In addition to the diversity of stressors endangering cell wall integrity, defects in peptidoglycan metabolism require rapid repair in order to prevent osmotic lysis, which can occur within minutes. Here, we review recent work that illuminates mechanisms that ensure robust peptidoglycan metabolism in response to persistent and acute environmental stress. Advances in our understanding of bacterial cell wall quality control promise to inform the development and use of antimicrobial agents that target the synthesis and remodeling of this essential macromolecule. IMPORTANCE Nearly all bacteria are encased in a peptidoglycan cell wall, an essential polysaccharide structure that protects the cell from osmotic rupture and reinforces cell shape. The integrity of this protective barrier must be maintained across the diversity of environmental conditions wherein bacteria replicate. However, at the cell surface, the cell wall and its synthesis machinery face unique challenges that threaten their integrity. Directly exposed to the extracellular environment, the peptidoglycan synthesis machinery encounters dynamic and extreme physicochemical conditions, which may impair enzymatic activity and critical protein-protein interactions. Biotic and abiotic stressors—including host defenses, cell wall active antibiotics, and predatory bacteria and phage—also jeopardize peptidoglycan integrity by introducing lesions, which must be rapidly repaired to prevent cell lysis. Here, we review recently discovered mechanisms that promote robust peptidoglycan synthesis during environmental and acute stress and highlight the opportunities and challenges for the development of cell wall active therapeutics.

Cell size is a complex trait, derived from both genetic and environmental factors. Environmental determinants of bacterial cell size identified to date primarily target assembly of cytosolic components of the cell division machinery. Whether certain environmental cues also impact cell size through changes in the assembly or activity of extracytoplasmic division proteins remains an open question. Here, we identify extracellular pH as a modulator of cell division and a significant determinant of cell size across evolutionarily distant bacterial species. In the Gram-negative model organism Escherichia coli, our data indicate environmental pH impacts the length at which cells divide by altering the ability of the terminal cell division protein FtsN to localize to the cytokinetic ring where it activates division. Acidic environments lead to enrichment of FtsN at the septum and activation of division at a reduced cell length. Alkaline pH inhibits FtsN localization and suppresses division activation. Altogether, our work reveals a previously unappreciated role for pH in bacterial cell size control.

The spirochete Borrelia burgdorferi causes Lyme disease. In some patients, an excessive, dysregulated proinflammatory immune response can develop in joints leading to persistent arthritis even after antibiotic therapy. In such patients, persistence of antigenic B. burgdorferi peptidoglycan (PG Bb ) fragments within joint tissues may contribute to immunopathogenesis pre- and post-antibiotic treatment. In live B. burgdorferi cells, the outer membrane shields the polymeric PG Bb sacculus from exposure to the immune system. However, unlike most diderm bacteria, B. burgdorferi releases PG Bb turnover products into its environment due to the absence of recycling activity. In this study, we identified the released PG Bb fragments using a mass spectrometry-based approach. By characterizing the l , d -carboxypeptidase activity of B. burgdorferi protein BB0605 (renamed DacA), we found that PG Bb turnover largely occurs at sites of PG Bb synthesis. In parallel, we demonstrated that the lytic transglycosylase activity associated with BB0259 (renamed MltS) releases PG Bb fragments with 1,6-anhydro bond on their N -acetylmuramyl residues. Stimulation of human cell lines with various synthetic PG Bb fragments revealed that 1,6-anhydromuramyl-containing PG Bb fragments are poor inducers of a NOD2-dependent immune response relative to their hydrated counterparts found in the polymeric PG Bb isolated from dead bacteria. We also showed that the activity of the human N -acetylmuramyl- l -alanine amidase PGLYRP2, which reduces the immunogenicity of PG Bb material, is low in joint (synovial) fluids relative to serum. Altogether, our findings suggest that MltS activity helps B. burgdorferi evade PG-based immune detection by NOD2 during growth despite shedding PG Bb fragments and that PG Bb -induced immunopathology likely results from host sensing of PG Bb material from dead (lysed) spirochetes. Additionally, our results suggest the possibility that natural variation in PGLYRP2 activity may contribute to differences in susceptibility to PG-induced inflammation across tissues and individuals.

Resident bacterial communities (microbiota) and host antimicrobial peptides (AMPs) are both essential components of normal host innate immune responses that limit infection and pathogen induced inflammation. However, their interdependence has not been investigated in the context of urinary tract infection (UTI) susceptibility. Here, we explored the interrelationship between the urinary microbiota and host AMP responses as mechanisms for UTI risk. Using prospectively collected day of surgery (DOS) urine specimens from female pelvic floor surgery participants, we report that the relative abundance and/or frequency of specific urinary microbiota distinguished between participants who did or did not develop a post-operative UTI. Furthermore, UTI risk significantly correlated with both specific urinary microbiota and β-defensin AMP levels. Finally, urinary AMP hydrophobicity and protease activity were greater in participants who developed UTI, and correlated positively with both UTI risk and pelvic floor symptoms. These data demonstrate an interdependency between the urinary microbiota, AMP responses and symptoms, and identify a potential mechanism for UTI risk. Assessment of bacterial microbiota and host innate immune AMP responses in parallel may identify increased risk of UTI in certain populations.

Skin and surgical infections due to Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii are causes of patient morbidity and increased healthcare costs. These organisms grow planktonically and as biofilms, and many strains exhibit antibiotic resistance. This study examines the antibacterial and anti-biofilm activity of glycerol monolaurate (GML), as solubilized in a non-aqueous vehicle (5% GML Gel), as a novel, broadly-active topical antimicrobial. The FDA has designated GML as generally recognized as safe for human use, and the compound is commonly used in the cosmetic and food industries. In vitro, bacterial strains in broths and biofilms were exposed to GML Gel, and effects on bacterial colony-forming units (CFUs) were assessed. In vivo,subcutaneous incisions were made in New Zealand white rabbits; the incisions were closed with four sutures. Bacterial strains were painted onto the incision sites, and then GML Gel or placebo was liberally applied to cover the sites completely. Rabbits were allowed to awaken and were examined for CFUs as a function of exposure time. In vitro, GML Gel was bactericidal for all broth culture and biofilm organisms in <1 hour and <4 hour, respectively; no CFUs were detected after the entire 24 h test period. In vivo, GML Gel inhibited bacterial growth in the surgical incision sites, compared to no growth inhibition in controls. GML Gel significantly reduced inflammation, as viewed by lack of redness in and below the incision sites. Our findings suggest that 5% GML Gel is useful as a potent topical antibacterial and anti-inflammatory agent for prevention of infections.

Following the discovery of the collective human urinary microbiota, important knowledge gaps remain, including the stability and variability of this microbial niche over time. Initial urinary studies preferentially utilized samples obtained by transurethral catheterization to minimize contributions from vulvovaginal microbes. However, catheterization has the potential to alter the urinary microbiota; therefore, voided specimens are preferred for longitudinal studies. In this report, we describe microbial findings obtained by daily assessment over 3 months in a small cohort of adult women. We found that, similarly to vaginal microbiotas, lower urinary tract (LUT) microbiotas are dynamic, with changes relating to several factors, particularly menstruation and vaginal intercourse. Our study results show that LUT microbiotas are both dynamic and resilient. They also offer novel opportunities to target LUT microbiotas by preventative or therapeutic means, through risk and/or protective factor modification. Temporal dynamics of certain human microbiotas have been described in longitudinal studies; variability often relates to modifiable factors or behaviors. Early studies of the urinary microbiota preferentially used samples obtained by transurethral catheterization to minimize vulvovaginal microbial contributions. Whereas voided specimens are preferred for longitudinal studies, the few studies that reported longitudinal data were limited to women with lower urinary tract (LUT) symptoms, due to ease of accessing a clinical population for sampling and the impracticality and risk of collecting repeated catheterized urine specimens in a nonclinical population. Here, we studied the microbiota of the LUT of nonsymptomatic, premenopausal women using midstream voided urine (MSU) specimens to investigate relationships between microbial dynamics and personal factors. Using 16S rRNA gene sequencing and a metaculturomics method called e xpanded q uantitative u rine c ulture (EQUC), we characterized the microbiotas of MSU and periurethral swab specimens collected daily for approximately 3 months from a small cohort of adult women. Participants were screened for eligibility, including the ability to self-collect paired urogenital specimens prior to enrollment. In this population, we found that measures of microbial dynamics related to specific participant-reported factors, particularly menstruation and vaginal intercourse. Further investigation of the trends revealed differences in the composition and diversity of LUT microbiotas within and across participants. These data, in combination with previous studies showing relationships between the LUT microbiota and LUT symptoms, suggest that personal factors relating to the genitourinary system may be an important consideration in the etiology, prevention, and/or treatment of LUT disorders. IMPORTANCE Following the discovery of the collective human urinary microbiota, important knowledge gaps remain, including the stability and variability of this microbial niche over time. Initial urinary studies preferentially utilized samples obtained by transurethral catheterization to minimize contributions from vulvovaginal microbes. However, catheterization has the potential to alter the urinary microbiota; therefore, voided specimens are preferred for longitudinal studies. In this report, we describe microbial findings obtained by daily assessment over 3 months in a small cohort of adult women. We found that, similarly to vaginal microbiotas, lower urinary tract (LUT) microbiotas are dynamic, with changes relating to several factors, particularly menstruation and vaginal intercourse. Our study results show that LUT microbiotas are both dynamic and resilient. They also offer novel opportunities to target LUT microbiotas by preventative or therapeutic means, through risk and/or protective factor modification.

Introduction and hypothesis Representatives of two classes of oral medication are often used to treat urgency urinary incontinence (UUI): solifenacin, an M3-receptor-selective antimuscarinic, and mirabegron, a beta-3 agonist. Two previous asynchronous drug-specific studies suggested different interactions between these medications and the urobiome despite identical methodologies, including recruitment, sample procurement, medication dose escalation strategy, determination of 12-week responders versus nonresponders, and data collection. This analysis compares data from these two studies using a uniform analytic approach. Methods Urine was collected aseptically via transurethral catheter from consenting participants for subsequent processing by the Expanded Quantitative Urine Culture (EQUC) protocol in two cohorts ( n =50 and n =47) that were demographically similar. Species accumulation curves were generated to compare the total number of unique species detected. Indices that measure richness, evenness, and/or abundance were used to compare alpha (within sample) diversity. The Bray–Curtis Dissimilarity Index was used to determine between sample (beta) diversity. Results The majority of the 40 species detected in the pre-treatment urobiomes were detected in both cohorts. Both pre-treatment urobiomes were substantially similar in species richness, evenness, and diversity. Differences in pre-treatment urobiomes were associated with treatment response for solifenacin-treated participants only. In contrast, the pre-treatment urobiomes of mirabegron-treated participants were not associated with treatment response. Changes in the post-treatment urobiomes were detected in both cohorts with an increase in richness for both solifenacin (5-mg dose only) and mirabegron. Conclusions Pre-treatment urobiome characteristics were associated with treatment response in participants treated with solifenacin, but not mirabegron. Differences exist in urobiome response after treatment with two medications that have known differences in mechanism of action.

Introduction and hypothesisWomen have a 20% risk of developing a urinary tract infection (UTI) following urogynecologic surgery. This study assessed the association of postoperative UTI with bacteria in preoperative samples of catheterized urine.MethodsImmediately before surgery, vaginal swabs, perineal swabs, and catheterized urine samples were collected, and the V4 region of the 16S ribosomal RNA (rRNA) gene was sequenced. The cohort was dichotomized in two ways: (1) standard day-of-surgery urine culture result (positive/negative), and (2) occurrence of postoperative UTI (positive/negative). Characteristics of bladder, vaginal, and perineal microbiomes were assessed to identify factors associated with postoperative UTI.ResultsEighty-seven percent of the 104 surgical patients with pelvic organ prolapse/urinary incontinence (POP/UI) were white; mean age was 57 years. The most common genus was Lactobacillus, with a mean relative abundance of 39.91% in catheterized urine, 53.88% in vaginal swabs, and 30.28% in perineal swabs. Two distinct clusters, based on dispersion of catheterized urine (i.e., bladder) microbiomes, had highly significant (p < 2.2–16) differences in age, microbes, and postoperative UTI risk. Postoperative UTI was most frequently associated with the bladder microbiome; microbes in adjacent pelvic floor niches also contributed to UTI risk. UTI risk was associated with depletion of Lactobacillus iners and enrichment of a diverse mixture of uropathogens.ConclusionsPostoperative UTI risk appears to be associated with preoperative bladder microbiome composition, where an abundance of L. iners appears to protect against postoperative UTI.