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Despite 50% of biology Ph.D. graduates being women, the number of women that advance in academia decreases at each level (e.g., from graduate to postdoctorate to tenure track). Recently, scientific societies and publishers have begun examining internal submissions data to evaluate representation and evaluation of women in their peer review processes; however, representation and attitudes differ by scientific field, and to date, no studies have investigated academic publishing in the field of microbiology. Using manuscripts submitted between January 2012 and August 2018 to the 15 journals published by the American Society for Microbiology (ASM), we describe the representation of women at ASM journals and the outcomes of their manuscripts. Senior women authors at ASM journals were underrepresented compared to global and society estimates of microbiology researchers. Additionally, manuscripts submitted by corresponding authors that were women received more negative outcomes than those submitted by men. These negative outcomes were somewhat mediated by whether or not the corresponding author was based in the United States and by the type of institution for United States-based authors. Nonetheless, the pattern for women corresponding authors to receive more negative outcomes on their submitted manuscripts held. We conclude with suggestions to improve the representation of women and decrease structural penalties against women.

Barriers in science and academia have prevented women from becoming researchers and experts that are viewed as equivalent to their colleagues who are men. We evaluated the participation and success of women researchers at ASM journals to better understand their success in the field of microbiology. We found that women are underrepresented as expert scientists at ASM journals. This is, in part, due to a combination of both low submissions from senior women authors and more negative outcomes on submitted manuscripts for women compared to men., Despite 50% of biology Ph.D. graduates being women, the number of women that advance in academia decreases at each level (e.g., from graduate to postdoctorate to tenure track). Recently, scientific societies and publishers have begun examining internal submissions data to evaluate representation and evaluation of women in their peer review processes; however, representation and attitudes differ by scientific field, and to date, no studies have investigated academic publishing in the field of microbiology. Using manuscripts submitted between January 2012 and August 2018 to the 15 journals published by the American Society for Microbiology (ASM), we describe the representation of women at ASM journals and the outcomes of their manuscripts. Senior women authors at ASM journals were underrepresented compared to global and society estimates of microbiology researchers. Additionally, manuscripts submitted by corresponding authors that were women received more negative outcomes than those submitted by men. These negative outcomes were somewhat mediated by whether or not the corresponding author was based in the United States and by the type of institution for United States-based authors. Nonetheless, the pattern for women corresponding authors to receive more negative outcomes on their submitted manuscripts held. We conclude with suggestions to improve the representation of women and decrease structural penalties against women.

Exploratory Science Center, Merck & Co , Inc , Cambridge, Massachusetts, United States of America Affiliation: Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America ORCID logo http://orcid org/0000-0003-3140-537X Patrick D Schloss * E-mail: pschloss@umich edu Affiliation: Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America ORCID logo http://orcid org/0000-0002-6935-4275 Introduction For most biologists, the ability to generate data has outpaced the ability to analyze those data In addition to building upon material from traditional coursework and staying current on the literature, Journal Clubs help strengthen skills in critical thinking, communication, and integrating the literature [11] Because most Journal Clubs occur on a regular schedule, they are effective by virtue of repeated practice With this model in mind, over the past four years we have experimented with creating a Code Club model with the goal of improving reproducible data analysis skills in a laboratory environment [ ]presenters were reluctant to offer to present again

The biomedical sciences have a problem retaining white women and underrepresented minorities in academia. Despite increases in the representation of these groups in faculty candidate pools, they are still underrepresented at the faculty level, particularly at the Full Professor level. The lack of diverse individuals at the Full Professor level contributes to the attrition of women and under-represented minorities, as it confirms unconscious biases. The presence of unconscious biases contribute to feelings of not belonging by trainees and are amplified by visual representation of who is presented as the “top scientist in their field”. Top scientists are not only defined by the attainment of Full Professorships, but also through invited seminar series. Invitations for faculty to present their research at other university departments is highly valued offer that provides an opportunity for collaborations and networking. However, if invited speakers do not represent the demographics of current trainees, these visual representations of successful scientists may contribute to decreased attitudes of self-identification as a scientist, ultimately resulting in trainees leaving the field or the academy. In this study, we compare invited-speaker demographics to the current trainee demographics in one microbiology and immunology department and find that trainees are not proportionally represented by speakers invited to the department. Our investigation prompted changes in policy for how invited speakers are selected in the future to invite a more diverse group of scientists. To facilitate this process, we developed a set of tips and a web-based resource that allows scientists, committees, and moderators to identify members of under-served groups. These resources can be easily adapted by other fields or sub-fields to promote inclusion and diversity at seminar series’, conferences, and colloquia.

Bacillus anthracis causes the disease anthrax, which is transmitted via its dormant, spore phase. However, conversion from bacillus to spore is a complex, energetically costly process that requires many nutrients, including iron. B. anthracis requires the siderophore petrobactin to scavenge iron from host environments. We show that, in the Sterne strain, petrobactin is required for efficient sporulation, even when ample iron is available. The petrobactin biosynthesis operon is expressed during sporulation, and petrobactin is biosynthesized during growth in high-iron sporulation medium, but instead of being exported, the petrobactin remains intracellular to protect against oxidative stress and improve sporulation. It is also required for full growth and sporulation in blood (bovine), an essential step for anthrax transmission between mammalian hosts., Bacillus anthracis is a Gram-positive bacillus that under conditions of environmental stress, such as low nutrients, can convert from a vegetative bacillus to a highly durable spore that enables long-term survival. The sporulation process is regulated by a sequential cascade of dedicated transcription factors but requires key nutrients to complete, one of which is iron. Iron acquisition by the iron-scavenging siderophore petrobactin is required for vegetative growth of B. anthracis under iron-depleted conditions and in the host. However, the extent to which petrobactin is involved in spore formation is unknown. This work shows that efficient in vitro sporulation of B. anthracis requires petrobactin, that the petrobactin biosynthesis operon (asbA to -F) is induced prior to sporulation, and that the siderophore itself associates with spores. Petrobactin is also required for oxidative stress protection during late-stage growth and for wild-type levels of sporulation in sporulation medium. Sporulation in bovine blood was found to be petrobactin dependent. Collectively, the in vitro contributions of petrobactin to sporulation as well as growth imply that petrobactin may be required for B. anthracis transmission via the spore during natural infections, in addition to its key known functions during active anthrax infections.

The dramatic, rapid growth of Bacillus anthracis that occurs during systemic anthrax implies a crucial requirement for the efficient acquisition of iron. While recent advances in our understanding of B. anthracis iron acquisition systems indicate the use of strategies similar to other pathogens, this review focuses on unique features of the major siderophore system, petrobactin. Ways that petrobactin differs from other siderophores include: A. unique ferric iron binding moieties that allow petrobactin to evade host immune proteins; B. a biosynthetic operon that encodes enzymes from both major siderophore biosynthesis classes; C. redundancy in membrane transport systems for acquisition of Fe-petrobactin holo-complexes; and, D. regulation that appears to be controlled predominately by sensing the host-like environmental signals of temperature, CO2 levels and oxidative stress, as opposed to canonical sensing of intracellular iron levels. We argue that these differences contribute in meaningful ways to B. anthracis pathogenesis. This review will also outline current major gaps in our understanding of the petrobactin iron acquisition system, some projected means for exploiting current knowledge, and potential future research directions. This article is protected by copyright. All rights reserved.

Clostridium difficile (C. difficile) is an anaerobic gram-positive pathogen that is the leading cause of nosocomial bacterial infection globally. C. difficile infection (CDI) typically occurs after ingestion of infectious spores by a patient that has been treated with broad-spectrum antibiotics. While CDI is a toxin-mediated disease, transmission and pathogenesis are dependent on the ability to produce viable spores. These spores must become metabolically active (germinate) in order to cause disease. C. difficile spore germination occurs when spores encounter bile salts and other co-germinants within the small intestine, however, the germination signaling cascade is unclear. Here we describe a signaling role for Ca2+ during C. difficile spore germination and provide direct evidence that intestinal Ca2+ coordinates with bile salts to stimulate germination. Endogenous Ca2+ (released from within the spore) and a putative AAA+ ATPase, encoded by Cd630_32980, are both essential for taurocholate-glycine induced germination in the absence of exogenous Ca2+. However, environmental Ca2+ replaces glycine as a co-germinant and circumvents the need for endogenous Ca2+ fluxes. Cd630_32980 is dispensable for colonization in a murine model of C. difficile infection and ex vivo germination in mouse ileal contents. Calcium-depletion of the ileal contents prevented mutant spore germination and reduced WT spore germination by 90%, indicating that Ca2+ present within the gastrointestinal tract plays a critical role in C. difficile germination, colonization, and pathogenesis. These data provide a biological mechanism that may explain why individuals with inefficient intestinal calcium absorption (e.g., vitamin D deficiency, proton pump inhibitor use) are more prone to CDI and suggest that modulating free intestinal calcium is a potential strategy to curb the incidence of CDI., Author summary The anaerobic, spore-forming bacterium Clostridium difficile (C. difficile) is a prominent pathogen in hospitals worldwide and the leading cause of nosocomial diarrhea. Numerous risk factors are associated with C. difficile infections (CDIs) including: antibiotics, advanced age, vitamin D deficiency, and proton pump inhibitors. Antibiotic use disrupts the intestinal microbiota allowing for C. difficile to colonize, however, why these other risk factors increase CDI incidence is unclear. Notably, deficient intestinal calcium absorption (i.e., increased calcium levels) is associated with these risk factors. In this work, we investigate the role of calcium in C. difficile spore germination. C. difficile spores are the infectious particles and they must become metabolically active (germinate) to cause disease. Here, we show that calcium is required for C. difficile germination, specifically activating the key step of cortex hydrolysis, and that this calcium can be derived from either within the spore or the environment. We also demonstrate that intestinal calcium is required for efficient spore germination in vivo, suggesting that intestinal concentrations of other co-germinants are insufficient to induce C. difficile germination. Collectively, these data provide a mechanism that explains the strong clinical correlations between increased intestinal calcium levels and risk of CDI.

Background The prevention of child mortality through immunization is one of the most cost-effective and widely applied public health interventions. In Ethiopia, the Expanded Program on Immunization (EPI) schedule is rarely completed as planned and the full immunization rate is only 24 %. The objective of this study was to identify determinant factors of incomplete childhood immunization in Arbegona district, Sidama zone, southern Ethiopia. Methods A community based unmatched case-control study was undertaken among randomly selected children aged 12 to 23 months and with a total sample size of 548 (183 cases and 365 controls). A multi-stage sampling technique was used to get representative cases and controls. Data was collected using a structured questionnaire and analyzed using SPSS version 16 statistical software. Bivariate and multiple logistic regression analyses were done to identify independent factors for incomplete immunization status of children. Qualitative data were also generated and analyzed using thematic framework. Results The incomplete immunization status of children was significantly associated with young mothers (AOR = 9.54; 95 % CI = 5.03, 18.09), being born second to fourth (AOR = 3.64; 95 % CI = 1.63, 8.14) and being born fifth or later in the family (AOR = 5.27; 95 % CI = 2.20, 12.64) as compared to being born first, a mother’s lack of knowledge about immunization benefits (AOR = 5.51; 95 % CI = 1.52, 19.94) and a mother’s negative perception of vaccine side effects (AOR = 1.92; 95 % CI = 1.01, 3.70). The qualitative finding revealed that the migration of mothers and unavailability of vaccines on appointed immunization dates were the major reasons for partial immunization of children. Conclusion To reduce the number of children with incomplete immunization status, the Arbegona district needs to consider specific planning for mothers with these risk profiles. A focus on strengthening health communication activities to raise immunization awareness and address concerns of vaccine side effects at community level is also needed. This could be achieved through integrating the immunization service to other elements of primary health care. Electronic supplementary material The online version of this article (doi:10.1186/s12889-015-2678-1) contains supplementary material, which is available to authorized users.

During the late stages of systemic anthrax, Bacillus anthracis grows rapidly in the host bloodstream. To identify potential genes necessary for this observed rapid growth, we defined the transcriptional profile of B. anthracis during in vitro growth in bovine blood. Genome-wide transcriptome analysis indicated that B. anthracis undergoes significant changes in its transcriptome profile during growth in blood, including the differential regulation of genes associated both with metabolism and known virulence factors. Collectively, these data provide a framework for future studies identifying specific B. anthracis factors required for growth in the mammalian bloodstream.

On 22 October 2015, the University of Michigan Department of Microbiology and Immunology became the twelfth Milestones in Microbiology site designated by ASM. The Milestones program, established to promote greater awareness and appreciation of microbiology, recognizes institutions with a strong history of significant contributions advancing the field of microbiology.

If there's a hot topic in microbiology, it's bacterial interaction and communication. Bacteria “talk” to each other using a complex chemical language we are only just beginning to understand. Quorum sensing allows communication between spatially separated cells of similar species. Functioning similarly, bacteriocins warn nonimmune bacteria away from a bacterium's established niche. Type VI secretion systems also help a bacterium protect its niche, but by initiating contact between cells. Here, I'll describe another instance of cell-to-cell interaction where bacteria don't just communicate, but also heal.