Biology subjects

Hogins, J.

Publications and source records attributed to Hogins, J..

7 recordsLinked to original sources

bioRxiv2026

PREFERENTIAL INVASION OF DIFFERENTIATED BLADDER CARCINOMA CELLS BY FLAGELLATED GROUP B2 ESCHERICHIA COLI

Phylogenetic group B2 Escherichia coli is associated with urinary tract infections and other pathologies, but the basis for this phylogenetic skew is not understood. One aspect of urinary tract infections is binding to and entering uroepithelial cells. To test whether a phylogenetic skew exists for cell invasion, we examined invasion of 10 E. coli strains from three phylogenetic groups into CRL2169 and HTB-9 cells, which are derived from grade 1 and grade 2 bladder carcinomas, respectively. The top four strains that invaded CRL2169 were from group B2: three of these strains had more flagella gene transcripts than the other seven strains. The seven strains that invaded HTB-9 were from different phylogenetic groups. For the model uropathogenic group B2 strain UTI89, which expresses pili over flagella, loss of flagella or pili impacted invasion into CRL2169 to similar extents, but loss of pili had a greater effect on invasion into HTB-9 and a murine infection model than loss of flagella. A hyperflagellated variant of a group A strain did not invade either cell line better than the parental strain. Reported transcript differences, which were confirmed experimentally, showed that CRL2169 was more differentiated. The endocytosis stimulator tanshinone enhanced invasion into HTB-9, but not into CRL2169, which suggests differences in endocytic pathways and is consistent with differences in differentiation states. If the initial or recurring event in urinary tract infection is invasion into differentiated urothelial cells, as opposed to tight junctions, then the role of flagella may have been underestimated.

molecular biology↗

bioRxiv2025

Enterococcus faecalis Influences the Transcription and Metabolism of Pathogenic Escherichia coli when Grown in Co-Culture

UTI involves bacterial growth in the disparate environments of the bladder and within uroepithelial cells. The bladder is a low-nutrient environment that nonetheless supports rapid growth. Phylogenetic group B2 Escherichia coli (Ec) is frequently isolated from urinary tract infection (UTI) patients. Non-B2 strains have also been isolated and are often co-isolated with Enterococcus faecalis (Ef). We characterized the interaction between three co-isolated Ec-Ef pairs and other Ec-Ef combinations in a nutrient-rich medium which was intended to emulate the rapid growth condition of the bladder. In this medium, Ef had little effect on Ec growth but resulted in major transcriptome differences. Ef affected the non-B2 and B2 strains differently. For the non-B2 Ec strains, Ef induced transcript for genes whose products degrade ornithine via putrescine to succinate which is subsequently metabolized by the TCA cycle. For a control B2 Ec strain, Ef induced transcripts for growth rate-associated genes of macromolecular synthesis, and for similar metabolic enzymes, except for those that degrade putrescine to succinate. Unexpectedly, Ef induced transcripts for glyoxylate shunt enzymes in both non-B2 and B2 Ec strains. The bacterial disparate and constantly changing environments during UTI suggest the potential for different types of Ec-Ef interactions. Our results provide evidence for nutrient cross-feeding as one type of Ec-Ef interaction.

microbiology↗

bioRxiv2025

Daily and Weekly Fluctuations in the Microbiome of the Urinary Tract of Postmenopausal Women with No History of Urinary Tract Infections

At least half of all women will experience a urinary tract infection (UTI) in their lifetime. Age, sexual activity, hormonal status, and the urinary tract microbiome (urobiome) contribute to the probability of infection. While studies have assessed urobiome composition during and after infection, no study has tracked the daily and weekly fluctuations of healthy urobiomes to determine urobiome stability. In this study, we sampled the clean catch urine of 3 women with no history of UTIs over the span of two weeks sampling three times a day on two days each week to track urobiome changes, and whether the urobiome in individuals with no UTI history resembles that of individuals after a UTI. Two participants were dominantly colonized by Lactobacillus while the third had a more diverse set of taxa albeit at a lower total amount of bacteria. We previously reported that the urine from only one of the less diverse urobiomes supported the growth of recently isolated uropathogenic Escherichia coli or Enterococcus faecalis, while the other two participants urines did not support growth. We conclude that 1) urobiomes exist in healthy post-menopausal women 2) these urobiomes have a stable and robust community structure and 3) a combination of colonization resistance, including nutrient limitation, and urobiome structure contributes to resistance to UTIs. ImportancePresented here is the first analysis of urinary tract microbiomes (urobiome) of post-menopausal women with no history of urinary tract infections collected at multiple times. These data contribute to the growing understanding of urobiomes of post-menopausal women during a healthy state. Minimal fluctuations were observed on an individual basis, confirming that the time of day or day of the week has no impact on the findings in longitudinal urine sample studies.

genetics↗

bioRxiv2024

Control of pili synthesis and putrescine homeostasis in Escherichia coli

Polyamines are biologically ubiquitous cations that bind to nucleic acids, ribosomes, and phospholipids and, thereby, modulate numerous processes, including surface motility in Escherichia coli. We characterized the metabolic pathways that contribute to polyamine-dependent control of surface motility in the commonly used strain W3110 and the transcriptome of a mutant lacking a putrescine synthetic pathway that was required for surface motility. Genetic analysis showed that surface motility required type 1 pili, the simultaneous presence of two independent putrescine anabolic pathways, and modulation by putrescine transport and catabolism. An immunological assay for FimA--the major pili subunit, reverse transcription quantitative PCR of fimA, and transmission electron microscopy confirmed that pili synthesis required putrescine. Comparative RNAseq analysis of a wild type and {Delta}speB mutant which exhibits impaired pili synthesis showed that the latter had fewer transcripts for pili structural genes and for fimB which codes for the phase variation recombinase that orients the fim operon promoter in the ON phase, although loss of speB did not affect the promoter orientation. Results from the RNAseq analysis also suggested (a) changes in transcripts for several transcription factor genes that affect fim operon expression, (b) compensatory mechanisms for low putrescine which implies a putrescine homeostatic network, and (c) decreased transcripts of genes for oxidative energy metabolism and iron transport which a previous genetic analysis suggests may be sufficient to account for the pili defect in putrescine synthesis mutants. We conclude that pili synthesis requires putrescine and putrescine concentration is controlled by a complex homeostatic network that includes the genes of oxidative energy metabolism.

microbiology↗

bioRxiv2022

Bacterial growth-promoting properties of pooled urine and individual urines from post-menopausal women with or without a urinary tract infection can vary substantially

Urinary tract infections (UTIs), mostly caused by uropathogenic E. coli (UPEC), are common bacterial infections that affect a majority of women and often recur. Genomic and transcriptomic analyses have not identified a common set of virulence genes which has suggested conserved virulence functions instead of virulence genes, multiple virulence mechanisms, and complex host-pathogen interactions. One aspect of the host-pathogen interaction is rapid UPEC growth in urine in vivo. When bacteria are grown in pooled urine, an averaged urine is assumed to diminish individual variation. We grew a non-pathogenic and pathogenic E. coli strains in urine from individuals who never had a UTI, had a UTI history but no current infection, and had a UTI history with a current infection. Bacterial growth showed large variations in individual urines and pooled urine supported significantly more growth than predicted for never and history groups but not the current group. UPEC strains, but not the non-pathogenic strain, were resistant to urinary inhibitory factors e.g., antimicrobial peptides based on an indirect inoculation-density effect assay. Total nutrient content tended to be higher in current group urine than never and history group urine. We propose that pooling optimizes a nutrient mixture in never and history group urines, which are often studied, whereas urine from current group individuals appear to have a more optimal nutrient mixture. We conclude that pooled urine is not "an average urine", and that the best comparisons of results between labs using pooled urine would also include results with a standardized synthetic urine.

microbiology↗

bioRxiv2020

The Nutrient and Energy Pathway Requirements for Surface Motility of Nonpathogenic and Uropathogenic Escherichia coli

Uropathogenic E. coli (UPEC) is the causative pathogen for most uncomplicated urinary tract infections. Flagellar-mediated motility is essential for virulence and colonization for ascending urinary tract infections. The appendage requirement for surface motility depends on the strain: nonpathogenic E. coli (NPEC) lab strains use pili, NPEC hypermotile derivatives use flagella, and UPEC strains use flagella. E. coli flagella-dependent surface motility had been previously shown to require glucose and amino acids. We examined the nutritional and pathway requirements of the NPEC strain W3110 for pili-dependent surface motility, which have not been previously examined. We then compared these requirements to those for two strains with flagella-dependent surface motility: a variant of W3110, W3110-J1, in which the synthesis of the activator of flagella synthesis has been upregulated and the UPEC strain UTI89. The glucose requirement for W3110 was higher than that for either W3110-J1 or UTI89. The pathways required for motility were also different. W3110, but not UTI89, required the Embden-Meyerhof-Parnas pathway via PfkA; conversely, UTI89, but not W3110, required the Entner-Doudoroff pathway, acetogenesis, and the TCA cycle. Glucose did not control flagella synthesis for W3110-J1 and UTI89. The differing requirements for surface motility are likely to reflect major metabolic differences between strains. The metabolic requirements for UTI89 motility suggest a specific adaptation to the urinary tract environment. IMPORTANCEUrinary tract infections affect over 50% of women and E. coli is the most common uropathogen. Virulence requires both pili and flagella, and both appendages can contribute to surface motility. Previous studies of E. coli surface motility did not consider the appendage requirement and the ability to switch the surface appendage. The nutrient and pathway requirements for surface motility of a non-pathogenic E. coli strain with either pili- or flagella-dependent surface motility and the uropathogen UTI89 were examined. Pili-dependent surface motility required glycolysis, while flagella-dependent motility required the TCA cycle and oxidative phosphorylation and was less dependent on glycolysis. The distinctive nutrient and pathway requirements for UTI89 motility probably result from metabolic adaptations to the urinary tract.

microbiology↗

bioRxiv2019

FIMBRIAE AND FLAGELLA MEDIATED SURFACE MOTILITY AND THE EFFECT OF GLUCOSE ON NONPATHOGENIC AND UROPATHOGENIC ESCHERICHIA COLI

We characterized the surface motility of nonpathogenic and pathogenic E. coli strains with respect to the appendage requirement, flagella versus fimbriae, and the glucose requirement. Nonpathogenic lab strains exhibited either slow or fast surface movement. The slow strains required type 1 fimbriae for movement, while the fast strains required flagella and had an insertion in the flhDC promoter region. Surface movement of three uropathogenic E. coli (UPEC) strains was fast and required flagella, but these strains did not have an insertion in the flhDC promoter region. We assessed swimming motility as an indicator of flagella synthesis and found that glucose inhibited swimming of the slow nonpathogenic strains but not of the fast nonpathogenic or pathogenic strains. Fimbriae-based surface motility requires glucose, which inhibits cyclic-AMP (cAMP) and flagella synthesis; therefore, we examined whether surface motility required cAMP. The surface motility of a slow, fimbriae-dominant, nonpathogenic strain did not require cAMP, which was expected because fimbriae synthesis does not require cAMP. In contrast, the surface motility of a faster, flagella-dominant, UPEC strain required cAMP, which was unexpected because swarming was unaffected by the presence of glucose. Electron microscopy verified the presence or absence of fimbriae or flagella. In summary, surface motilities of the nonpathogenic and uropathogenic E. coli strains of this study differed in the appendage used and the effects of glucose on flagella synthesis. IMPORTANCEUropathogenic Escherichia coli strains cause 80-90% of community-acquired urinary tract infections, and recurrent urinary tract infections, which can last for years, and often become antibiotic resistant. Urinary tract infections can be associated with intra-vesical lesions extending from localized trigonitis/cystitis to widely distributed pancystitis: motility may be a factor that distinguishes between these infection patterns. Nonpathogenic and uropathogenic E. coli were shown to exhibit fimbriae- and flagella-dependent surface motility, respectively, and the difference was attributed to altered control of flagella synthesis by glucose. Uropathogenic E. coli strains grow more rapidly in urine than nonpathogenic strains, which implies differences in metabolism. Understanding the basis for glucose-insensitive control of flagella-dependent motility could provide insight into uropathogenic E. coli metabolism and virulence.

microbiology↗