1
|
Liu X, Gilbert RG. Normal and abnormal glycogen structure - A review. Carbohydr Polym 2024; 338:122195. [PMID: 38763710 DOI: 10.1016/j.carbpol.2024.122195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/18/2024] [Accepted: 04/20/2024] [Indexed: 05/21/2024]
Abstract
Glycogen, a complex branched glucose polymer, is found in animals and bacteria, where it serves as an energy storage molecule. It has linear (1 → 4)-α glycosidic bonds between anhydroglucose monomer units, with branch points connected by (1 → 6)-α bonds. Individual glycogen molecules are referred to as β particles. In organs like the liver and heart, these β particles can bind into larger aggregate α particles, which exhibit a rosette-like morphology. The mechanisms and bonding underlying the aggregation process are not fully understood. For example, mammalian liver glycogen has been observed to be molecularly fragile under certain conditions, such as glycogen from diabetic livers fragmenting when exposed to dimethyl sulfoxide (DMSO), while glycogen from healthy livers is much less fragile; this indicates some difference, as yet unknown, in the bonding between β particles in healthy and diabetic glycogen. This fragility may have implications for blood sugar regulation, especially in pathological conditions such as diabetes.
Collapse
Affiliation(s)
- Xin Liu
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Zhongshan Biological Breeding Laboratory, and Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Agriculture, Yangzhou University, Yangzhou 225009, China; Centre for Nutrition & Food Sciences, Queensland Alliance for Agriculture & Food Innovations (QAAFI), The University of Queensland, QLD 4072, Australia
| | - Robert G Gilbert
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Zhongshan Biological Breeding Laboratory, and Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Agriculture, Yangzhou University, Yangzhou 225009, China; Centre for Nutrition & Food Sciences, Queensland Alliance for Agriculture & Food Innovations (QAAFI), The University of Queensland, QLD 4072, Australia.
| |
Collapse
|
2
|
Rahman N, Mian MF, Nazli A, Kaushic C. Human vaginal microbiota colonization is regulated by female sex hormones in a mouse model. Front Cell Infect Microbiol 2023; 13:1307451. [PMID: 38156321 PMCID: PMC10753781 DOI: 10.3389/fcimb.2023.1307451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 11/22/2023] [Indexed: 12/30/2023] Open
Abstract
Introduction Clinically, a Lactobacillus rich vaginal microbiota (VMB) is considered optimal for reproductive outcomes, while a VMB populated by anaerobes is associated with dysbiosis and the clinical condition bacterial vaginosis (BV), which is linked to increased susceptibility to sexually transmitted infections and adverse reproductive outcomes. Mouse models that mimic eubiotic and dysbiotic VMB are currently lacking but could play a critical role in improving protective interventions. Methods In this study, probiotic, eubiotic, and dysbiotic models were developed in C57BL/6 mice, using probiotic strains Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14, eubiotic Lactobacillus crispatus, or dysbiotic Gardnerella vaginalis strains. Endogenous sex hormones were manipulated by either ovariectomizing (OVX) mice or administering 17β-estradiol or progesterone pellets in OVX mice. Hormone-altered mice were inoculated with probiotic Lactobacillus species, L. crispatus, or G. vaginalis, and colonization was tracked using quantitative plating assays. Glycogen and MUC-1 levels in hormone-treated mice were determined with ELISA and MUC-1 staining. Results Following a single administration, L. rhamnosus and L. reuteri persisted in the mouse vaginal tract for up to eight days, L. crispatus persisted for up to three days, and G. vaginalis persisted for up to two days, as measured by quantitative plating assays and qPCR. Colonization of G. vaginalis was facilitated by the presence of mucin. The lack of endogenous hormones in OVX mice dramatically decreased VMB bacterial load compared to normal mice. None of the exogenous bacteria including Lactobacilli could colonize OVX mice for more than 24 hours. Treatment with 17β-estradiol but not progesterone restored the endogenous VMB and colonization with Lactobacilli and G. vaginalis. Interestingly, 17β-estradiol treated mice had significantly increased levels of glycogen compared to OVX and progesterone-treated mice. Discussion Based on the results, we have shown that estrogen played a significant role in the ability for human VMB species to colonize in our mouse models, potentially through a glycogen mediated mechanism. These results suggest there is a dynamic interaction between sex hormones and the VMB, which can affect bacterial diversity and the ability for a VMB to colonize.
Collapse
Affiliation(s)
- Nuzhat Rahman
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Center, Michael G. DeGroote Center for Learning and Discovery, McMaster University, Hamilton, ON, Canada
| | - M. Firoz Mian
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Center, Michael G. DeGroote Center for Learning and Discovery, McMaster University, Hamilton, ON, Canada
| | - Aisha Nazli
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Center, Michael G. DeGroote Center for Learning and Discovery, McMaster University, Hamilton, ON, Canada
| | - Charu Kaushic
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Center, Michael G. DeGroote Center for Learning and Discovery, McMaster University, Hamilton, ON, Canada
| |
Collapse
|
3
|
Jenkins DJ, Woolston BM, Hood-Pishchany MI, Pelayo P, Konopaski AN, Quinn Peters M, France MT, Ravel J, Mitchell CM, Rakoff-Nahoum S, Whidbey C, Balskus EP. Bacterial amylases enable glycogen degradation by the vaginal microbiome. Nat Microbiol 2023; 8:1641-1652. [PMID: 37563289 PMCID: PMC10465358 DOI: 10.1038/s41564-023-01447-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 07/11/2023] [Indexed: 08/12/2023]
Abstract
The human vaginal microbiota is frequently dominated by lactobacilli and transition to a more diverse community of anaerobic microbes is associated with health risks. Glycogen released by lysed epithelial cells is believed to be an important nutrient source in the vagina. However, the mechanism by which vaginal bacteria metabolize glycogen is unclear, with evidence implicating both bacterial and human enzymes. Here we biochemically characterize six glycogen-degrading enzymes (GDEs), all of which are pullanases (PulA homologues), from vaginal bacteria that support the growth of amylase-deficient Lactobacillus crispatus on glycogen. We reveal variations in their pH tolerance, substrate preferences, breakdown products and susceptibility to inhibition. Analysis of vaginal microbiome datasets shows that these enzymes are expressed in all community state types. Finally, we confirm the presence and activity of bacterial and human GDEs in cervicovaginal fluid. This work establishes that bacterial GDEs can participate in the breakdown of glycogen, providing insight into metabolism that may shape the vaginal microbiota.
Collapse
Affiliation(s)
- Dominick J Jenkins
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Benjamin M Woolston
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Department of Chemical Engineering, Northeastern University, Boston, MA, USA
| | - M Indriati Hood-Pishchany
- Division of Infectious Diseases and Division of Gastroenterology, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Paula Pelayo
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | | | - M Quinn Peters
- Department of Chemistry, Seattle University, Seattle, WA, USA
| | - Michael T France
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jacques Ravel
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Caroline M Mitchell
- Vincent Center for Reproductive Biology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Seth Rakoff-Nahoum
- Division of Infectious Diseases and Division of Gastroenterology, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA.
- Department of Microbiology, Harvard Medical School, Boston, MA, USA.
| | | | - Emily P Balskus
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
| |
Collapse
|
4
|
Navarro S, Abla H, Delgado B, Colmer-Hamood JA, Ventolini G, Hamood AN. Glycogen availability and pH variation in a medium simulating vaginal fluid influence the growth of vaginal Lactobacillus species and Gardnerella vaginalis. BMC Microbiol 2023; 23:186. [PMID: 37442975 PMCID: PMC10339506 DOI: 10.1186/s12866-023-02916-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Glycogen metabolism by Lactobacillus spp. that dominate the healthy vaginal microbiome contributes to a low vaginal pH (3.5-4.5). During bacterial vaginosis (BV), strict and facultative anaerobes including Gardnerella vaginalis become predominant, leading to an increase in the vaginal pH (> 4.5). BV enhances the risk of obstetrical complications, acquisition of sexually transmitted infections, and cervical cancer. Factors critical for the maintenance of the healthy vaginal microbiome or the transition to the BV microbiome are not well defined. Vaginal pH may affect glycogen metabolism by the vaginal microflora, thus influencing the shift in the vaginal microbiome. RESULTS The medium simulating vaginal fluid (MSVF) supported growth of L. jensenii 62G, L. gasseri 63 AM, and L. crispatus JV-V01, and G. vaginalis JCP8151A at specific initial pH conditions for 30 d. L. jensenii at all three starting pH levels (pH 4.0, 4.5, and 5.0), G. vaginalis at pH 4.5 and 5.0, and L. gasseri at pH 5.0 exhibited the long-term stationary phase when grown in MSVF. L. gasseri at pH 4.5 and L. crispatus at pH 5.0 displayed an extended lag phase over 30 d suggesting inefficient glycogen metabolism. Glycogen was essential for the growth of L. jensenii, L. crispatus, and G. vaginalis; only L. gasseri was able to survive in MSVF without glycogen, and only at pH 5.0, where it used glucose. All four species were able to survive for 15 d in MSVF with half the glycogen content but only at specific starting pH levels - pH 4.5 and 5.0 for L. jensenii, L. gasseri, and G. vaginalis and pH 5.0 for L. crispatus. CONCLUSIONS These results suggest that variations in the vaginal pH critically influence the colonization of the vaginal tract by lactobacilli and G. vaginalis JCP8151A by affecting their ability to metabolize glycogen. Further, we found that L. jensenii 62G is capable of glycogen metabolism over a broader pH range (4.0-5.0) while L. crispatus JV-V01 glycogen utilization is pH sensitive (only functional at pH 5.0). Finally, our results showed that G. vaginalis JCP8151A can colonize the vaginal tract for an extended period as long as the pH remains at 4.5 or above.
Collapse
Affiliation(s)
- Stephany Navarro
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Habib Abla
- School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Betsaida Delgado
- Honors College, Texas Tech University, Lubbock, TX USA
- Woody L. Hunt School of Dental Medicine, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Jane A. Colmer-Hamood
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX USA
- Department of Medical Education, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Gary Ventolini
- Department of Obstetrics and Gynecology, Texas Tech University Health Sciences Center Permian Basin, Odessa, TX USA
| | - Abdul N. Hamood
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX USA
- Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX USA
| |
Collapse
|
5
|
Miao J, Regan J, Cai C, Palmer GE, Williams DL, Kruppa MD, Peters BM. Glycogen Metabolism in Candida albicans Impacts Fitness and Virulence during Vulvovaginal and Invasive Candidiasis. mBio 2023; 14:e0004623. [PMID: 36840583 PMCID: PMC10127583 DOI: 10.1128/mbio.00046-23] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 02/01/2023] [Indexed: 02/24/2023] Open
Abstract
The polymorphic fungus Candida albicans remains a leading cause of both invasive and superficial mycoses, including vulvovaginal candidiasis (VVC). Metabolic plasticity, including carbohydrate catabolism, confers fitness advantages at anatomical site-specific host niches. C. albicans possesses the capacity to accumulate and store carbohydrates as glycogen and can consume intracellular glycogen stores when nutrients become limited. In the vaginal environment, estrogen promotes epithelial glycogen accumulation and C. albicans colonization. However, whether these factors are mechanistically linked is unexplored. Here, we characterized the glycogen metabolism pathways in C. albicans and investigated whether these impact the long-term survival of C. albicans, both in vitro and in vivo during murine VVC, or virulence during systemic infection. SC5314 and 6 clinical isolates demonstrated impaired growth when glycogen was used as the sole carbon source, suggesting that environmental glycogen acquisition is limited. The genetic deletion and complementation of key genes involved in glycogen metabolism in Saccharomyces cerevisiae confirmed that GSY1 and GLC3, as well as GPH1 and GDB1, are essential for glycogen synthesis and catabolism in C. albicans, respectively. Potential compensatory roles for a glucoamylase encoded by SGA1 were also explored. Competitive survival assays revealed that gsy1Δ/Δ, gph1Δ/Δ, and gph1Δ/Δ sga1Δ/Δ mutants exhibited long-term survival defects in vitro under starvation conditions and in vivo during vaginal colonization. A complete inability to catabolize glycogen (gph1Δ/Δ sga1Δ/Δ) also rendered C. albicans significantly less virulent during disseminated infections. This is the first study fully validating the glycogen metabolism pathways in C. albicans, and the results further suggest that intracellular glycogen catabolism positively impacts the long-term fitness of C. albicans in nutrient deficient environments and is important for full virulence. IMPORTANCE Glycogen is a highly branched polymer of glucose and is used across the tree of life as an efficient and compact form of energy storage. Whereas glycogen metabolism pathways have been studied in model yeasts, they have not been extensively explored in pathogenic fungi. Using a combination of microbiologic, molecular genetic, and biochemical approaches, we reveal orthologous functions of glycogen metabolism genes in the fungal pathogen Candida albicans. We also provide evidence that extracellular glycogen poorly supports growth across the Candida species and clinical isolates. Competitive fitness assays reveal that the loss of glycogen synthesis or catabolism significantly impacts survival during both in vitro starvation and the colonization of the mouse vagina. Moreover, a global glycogen catabolism mutant is rendered less virulent during murine invasive candidiasis. Therefore, this work demonstrates that glycogen metabolism in C. albicans contributes to survival and virulence in the mammalian host and may be a novel antifungal target.
Collapse
Affiliation(s)
- Jian Miao
- Pharmaceutical Sciences Program, College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Jessica Regan
- Pharmaceutical Sciences Program, College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Chun Cai
- Department of Clinical Pharmacy and Translational Science, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Glen E. Palmer
- Department of Clinical Pharmacy and Translational Science, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee, USA
- Department of Microbiology, Immunology, and Biochemistry, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - David L. Williams
- Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, USA
- Center of Excellence in Inflammation, Infectious Disease, and Immunity, East Tennessee State University, Johnson City, Tennessee, USA
| | - Michael D. Kruppa
- Center of Excellence in Inflammation, Infectious Disease, and Immunity, East Tennessee State University, Johnson City, Tennessee, USA
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, USA
| | - Brian M. Peters
- Department of Clinical Pharmacy and Translational Science, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee, USA
- Department of Microbiology, Immunology, and Biochemistry, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| |
Collapse
|