Rosanne Hertzberger

Rosanne Hertzberger
Vrije Universiteit Amsterdam | VU · Amsterdam Institute for Molecules, Medicines and Systems

About

19
Publications
2,758
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
315
Citations
Citations since 2016
14 Research Items
300 Citations
20162017201820192020202120220204060
20162017201820192020202120220204060
20162017201820192020202120220204060
20162017201820192020202120220204060
Introduction
I am interested in the role of bacterial glycogen metabolism on vaginal health and disease. I study both clinical samples as well as vaginal bacteria in isolation, using anaerobic growth, proteomics and HPLC. My ultimate aim is to use our findings to improve treatment options for women with poor vaginal health in various stages of life. I follow an 'open kitchen science' approach sharing as much output as possible: data, methods, slides, posters, working hypotheses and results (+/-).
Skills and Expertise
Additional affiliations
July 2014 - May 2016
Washington University in St. Louis
Position
  • PostDoc Position
Description
  • research on influence of bacterial carbohydrate metabolism on vaginal host/microbe interactions.
April 2009 - July 2014
University of Amsterdam
Position
  • PhD Student
April 2009 - April 2013
NIZO food research
Position
  • PhD Student

Publications

Publications (19)
Article
Full-text available
Glycogen in the female lower reproductive tract is a major carbon source for colonization and acidification by common vaginal Lactobacillus species, such as Lactobacillus crispatus. Previously, we identified the amylopullulanase encoding gene pulA of Lactobacillus crispatus to correlate with the ability to autonomously utilize glycogen for growth....
Preprint
Full-text available
Glycogen in the female lower reproductive tract is a major carbon source for vaginal colonization and acidification by common vaginal Lactobacillus species, such as Lactobacillus crispatus. Previously we identified the pullulanase gene pulA in Lactobacillus crispatus, correlating with its ability to autonomously utilize glycogen for growth. Here we...
Preprint
Full-text available
Glycogen in the female lower reproductive tract is a major carbon source for vaginal colonization and acidification by common vaginal Lactobacillus species, such as Lactobacillus crispatus . Previously we identified the pullulanase gene pulA in Lactobacillus crispatus , correlating with its ability to autonomously utilize glycogen for growth. Here...
Presentation
Full-text available
Vaccinology Masterclass 2020 2-DAAGSE MASTERCLASS VACCINS Voor Specialisten en Onderzoekers in de Infectiebestrijding | 1 & 2 oktober 2020 | Almere Development and current insights related to vaccines “Learn from the past, act in the present and prepare for the future”
Article
Full-text available
Background A vaginal microbiota dominated by lactobacilli (particularly Lactobacillus crispatus) is associated with vaginal health, whereas a vaginal microbiota not dominated by lactobacilli is considered dysbiotic. Here we investigated whether L. crispatus strains isolated from the vaginal tract of women with Lactobacillus-dominated vaginal microb...
Poster
Full-text available
Glycogen is an abundant carbohydrate in the vagina of reproductive-age women. Levels of free glycogen vary depending on the makeup of the vaginal microbiota: women with bacterial vaginosis, a common dysbiosis with higher pH and few lactobacilli, generally have lower glycogen levels. This finding has led to the general assumption that lactobacilli d...
Preprint
Full-text available
Background: A vaginal microbiota dominated by lactobacilli (particularly Lactobacillus crispatus) is associated with vaginal health, whereas a vaginal microbiota not dominated by lactobacilli is considered dysbiotic. Here we investigated whether L. crispatus strains isolated from the vaginal tract of women with Lactobacillus-dominated vaginal micro...
Experiment Findings
Full-text available
Findings on type 1 pullulanase of Lactobacillus crispatus. More information http://www.reblab.org/ongoing-experiments-log/. Find accompanying data, protocol and sequences at: https://figshare.com/collections/REBLAB_Carbohydrate_active_enzymes_in_Lactobacillus_crispatus_-_a_possible_link_between_the_pullulanase_gene_and_growth_on_glycogen/4133819
Article
Full-text available
Inflammatory bowel disease (IBD) is a multifactorial chronic inflammatory disease of the gastrointestinal tract, characterized by cycles of acute flares, recovery and remission phases. Treatments for accelerating tissue restitution and prolonging remission are scarce, but altering the microbiota composition to promote intestinal homeostasis is cons...
Article
Full-text available
Intestinal infections are a global challenge, connected to malnutrition and inadequate hygiene in developing countries, and to expanding antibiotic resistance in developed countries. In general, a healthy host is capable of fighting off gut pathogens or at least to recover from infections quickly. The underlying protective mechanism, termed coloniz...
Article
Full-text available
Hydrogen peroxide production is a well-known trait of many bacterial species associated with the human body. In the presence of oxygen, the probiotic lactic acid bacterium Lactobacillus johnsonii NCC 533 excretes up to 1 mM H2O2, inducing growth stagnation and cell death. Disruption of genes commonly assumed to be involved in H2O2 production (e.g....
Article
Full-text available
Oxygen relieves the CO and acetate dependency of NCC 533. The probiotic NCC 533 is relatively sensitive to oxidative stress; the presence of oxygen causes a lower biomass yield due to early growth stagnation. We show however that oxygen can also be beneficial to this organism as it relieves the requirement for acetate and CO during growth. Both on...
Data
Superimposed image of baclight-stained microcolonies. Composite picture in which images of colonies after 7 hours of growth in environments that vary in oxygen and CO2 content are grouped. Images were thresholded, colors were assigned artificially and superimposed as described in Materials & Methods. (TIF)
Data
Presence of genes for pyruvate dehydrogenase or pyruvate formate lyase in Lactobacilli. Overview of pyruvate dehydrogenase and pyruvate formate lyase encoding gene prevalence in lactobacilli (Table A) and in species belonging to the Lactobacillus acidophilus group (Table 1B). If no gene was found, a BLAST search was performed using the protein sequ...
Data
Effect of catalase on aerobic growth. Figure 1: Growth of L. johnsonii NCC 533 in MRS medium supplemented with 0.5 mg/ml catalase (open symbols) and regular MRS medium (closed symbols) in either static tubes with limited headspace (round symbols) or in shake flasks (square symbols). Depicted are the averages of duplicate experiments ± standard erro...

Questions

Question (1)
Question
Dear Researchgate community,
I have been working on purification of an alpha-glycosidase activity from an unknown enzyme in an environmental sample. I have been using the GE ResourceQ column but activity is not present in any of the fractions. I have used buffer pH 8.0, tried a salt gradient in Tris-HCl (2M NaCl) as well as pH gradient in potassium phosphate buffer (8.0-3.0). I tried stabilising agents 10 mm betamercaptoethanol, 5% glycerol, and 5 mm CaCl2.
After cleaning the column with 2M NaOH, a large peak elutes. However, the enzyme is active and stable in all abovementioned conditions. The only time I managed to obtain active protein was when I forgot to increase the pH of my sample (which is highly acidic) and the activity ended up in the unbound fraction.
What's next? What would you do in my situation? I am thinking of trying size exclusion next but would love to hear your suggestions. Your answers here have been really helpful sofar. Thanks in advance!

Network

Cited By

Projects

Project (1)
Project
I am interested in the role of bacterial glycogen metabolism on vaginal health and disease. I study both clinical samples as well as vaginal bacteria in isolation, using anaerobic growth, proteomics and HPLC. My ultimate aim is to use our findings to improve treatment options for women with poor vaginal health in various stages of life. I follow an 'open kitchen science' approach sharing as much output as possible: data, methods, slides, posters, working hypotheses and results (+/-).