Comparison of lateral tail vein and retro-orbital venous sinus as routes of inoculation to study Group B streptococcal systemic infection.

Unlabelled: Murine models are commonly used to understand pathogen and host determinants of systemic infection. While these models have proven beneficial for uncovering bacterial mechanisms required for progression to invasive disease, it can be challenging to draw comparisons across studies as several different routes of infection are standardly used for these experiments. In this study, one of the leading bacterial meningeal pathogens, , or Group B (GBS), was used to compare experimental outcomes of two commonly used routes of hematogenous infection, lateral tail vein injection and retro-orbital venous sinus injection.

The impact of nutritional immunity on Group B streptococcal pathogenesis during wound infection.

Group B (GBS) is a Gram-positive pathobiont that can cause adverse health outcomes in neonates and vulnerable adult populations. GBS is one of the most frequently isolated bacteria from diabetic (Db) wound infections but is rarely found in the non-diabetic (nDb) wound environment. Previously, RNA sequencing of wound tissue from Db wound infections in diabetic mice showed increased expression of neutrophil factors, and genes involved in GBS metal transport such as the zinc (Zn), manganese (Mn), and putative nickel (Ni) import systems.

Enhanced Vulnerability of Diabetic Mice to Hypervirulent ST-17 Infection.

(Group B , GBS) is the leading cause of neonatal sepsis and meningitis but has been recently isolated from non-pregnant adults with underlying medical conditions like diabetes. Despite diabetes being a key risk factor for invasive disease, the pathological consequences during GBS infection remain poorly characterized. Here, we demonstrate the pathogenicity of the GBS90356-ST17 and COH1-ST17 strains in streptozotocin-induced diabetic mice.

Interrelated Effects of Zinc Deficiency and the Microbiome on Group B Streptococcal Vaginal Colonization.

Group B Streptococcus (GBS) in the vaginal tract is a risk factor for preterm birth and adverse pregnancy outcomes. GBS colonization is also transient in nature, which likely reflects the contributions of pathogen determinants, interactions with commensal flora, and host factors, making this environment particularly challenging to understand. Additionally, dietary zinc deficiency is a health concern on the global scale that is known to be associated with recurrent bacterial infection and increased rate of preterm birth or stillbirth.

Role of MUC5B during Group B Streptococcal Vaginal Colonization.

The female reproductive tract (FRT) is a complex environment, rich in mucin glycoproteins that form a dense network on the surface of the underlying epithelia. Group B Streptococcus (GBS) asymptomatically colonizes 25-30% of healthy women, but during pregnancy can cause ascending infection or be transmitted to the newborn during birth to cause invasive disease. Though the cervicovaginal mucosa is a natural site for GBS colonization, the specific interactions between GBS and mucins remain unknown.

Responses to chemical cross-talk between the Mycobacterium ulcerans toxin, mycolactone, and Staphylococcus aureus.

Buruli ulcer is a neglected tropical disease caused by the environmental pathogen, Mycobacterium ulcerans whose major virulence factor is mycolactone, a lipid cytotoxic molecule. Buruli ulcer has high morbidity, particularly in rural West Africa where the disease is endemic. Data have shown that infected lesions of Buruli ulcer patients can be colonized by quorum sensing bacteria such as Staphylococcus aureus, S.

The Virtual Streptococcal Seminar Series and Trainee Symposium: Adaptations of a Research Community during the COVID-19 Pandemic.

The COVID-19 pandemic has forced academic research communities to develop online means of learning, networking, and engaging in new research. To allow increased interaction and engagement of the streptococcal research community during the COVID-19 shutdown, we organized the Virtual Streptococcal Seminar Series and Virtual Streptococcal Trainee Symposium and advertised via e-mail and social media outlets. The seminar series initially met weekly on Thursdays at 12 pm Eastern Daylight Time and transitioned to monthly seminars, while the trainee symposium spanned 3 days in September 2020.

Identification of Zinc-Dependent Mechanisms Used by Group B To Overcome Calprotectin-Mediated Stress.

Nutritional immunity is an elegant host mechanism used to starve invading pathogens of necessary nutrient metals. Calprotectin, a metal-binding protein, is produced abundantly by neutrophils and is found in high concentrations within inflammatory sites during infection. Group B (GBS) colonizes the gastrointestinal and female reproductive tracts and is commonly associated with severe invasive infections in newborns such as pneumonia, sepsis, and meningitis.

Genome-Wide Mutagenesis Identifies Factors Involved in Enterococcus faecalis Vaginal Adherence and Persistence.

is a Gram-positive commensal bacterium native to the gastrointestinal tract and an opportunistic pathogen of increasing clinical concern. also colonizes the female reproductive tract, and reports suggest vaginal colonization increases following antibiotic treatment or in patients with aerobic vaginitis. Currently, little is known about specific factors that promote vaginal colonization and subsequent infection.

metal homeostasis alters cellular metabolism.

Streptococcus pneumoniae colonizes the human nasopharyngeal mucosa and is a leading cause of community-acquired pneumonia, acute otitis media, and bacterial meningitis. Metal ion homeostasis is vital to the survival of this pathogen across diverse biological sites and contributes significantly to colonization and invasive disease. Microarray and qRT-PCR analysis revealed an upregulation of an uncharacterized operon (SP1433-1438) in pneumococci subjected to metal-chelation by N,N,N',N'-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN).

Identification of Key Determinants of Staphylococcus aureus Vaginal Colonization.

is an important pathogen responsible for nosocomial and community-acquired infections in humans, and methicillin-resistant (MRSA) infections have continued to increase despite widespread preventative measures. can colonize the female vaginal tract, and reports have suggested an increase in MRSA infections in pregnant and postpartum women as well as outbreaks in newborn nurseries. Currently, little is known about specific factors that promote MRSA vaginal colonization and subsequent infection.

Determinants of Group B streptococcal virulence potential amongst vaginal clinical isolates from pregnant women.

Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is a Gram-positive bacterium isolated from the vaginal tract of approximately 25% of women. GBS colonization of the female reproductive tract is of particular concern during pregnancy as the bacteria can invade gestational tissues or be transmitted to the newborn during passage through the birth canal. Infection of the neonate can result in life-threatening pneumonia, sepsis and meningitis.

Biochemical but not compositional recovery of skin mucosal microbiome communities after disruption.

Background: The microbiomes of animals are complex communities that strongly affect the health of the hosts. Microbiomes on mucosal surfaces have the highest densities and most extensive biochemical exchanges with the hosts. Although antibiotics are potent tools to manage infections, they can disrupt the normal microbiota, causing numerous side effects.