Evolution

TWiM #217: The Chronicles of Narnaviruses

Podcast and Annotation Information

  • Annotation by  Basheer Alam, Elizabeth Fowler, Fatma Youssef and Myrna Rezcallah  
  • Podcast audio by TWiM: Listen to TWiM #217 Podcast
  • Podcast transcript by Otter.ai and edited by Laurel Thompson and Hannah Harris: Access Podcast Transcripts
  • Papers Discussed:
    • Forsyth VS, Himpsl SD, Smith SN, Sarkissian CA, Mike LA, Stocki JA, Sintsova A, Alteri CJ, Mobley HLT. 2020. Optimization of an Experimental Vaccine To Prevent Escherichia coli Urinary Tract Infection. mBio. 11(2):e00555-20. doi: 10.1128/mBio.00555-20.
    • Espino-Vázquez AN, Bermúdez-Barrientos JR, Cabrera-Rangel JF, Córdova-López G, Cardoso-Martínez F, Martínez-Vázquez A, Camarena-Pozos DA, Mondo SJ, Pawlowska TE, Abreu-Goodger C, Partida-Martínez LP. 2020. Narnaviruses: novel players in fungal-bacterial symbioses. ISME J.14(7):1743-1754. doi: 10.1038/s41396-020-0638-y.

1. Paper Abstracts

1.1. Snippet paper; discussion starts at 2:53 minutes

The Most Interesting Things (according to students)

The study explored a wide range of adjuvants, including alum, MPLA, CpG, polyIC, and dmLT, to enhance immune responses and optimize vaccine efficacy.Different vaccination routes (intramuscular, intranasal, subcutaneous) showed varying levels of effectiveness, highlighting the importance of delivery methods in vaccine development. One in 40 women will experience a recurrent infection.

“Urinary tract infections (UTI) affect half of all women at least once during their lifetime. The rise in the numbers of extended-spectrum beta-lactamase-producing strains and the potential for carbapenem resistance within uropathogenic Escherichia coli (UPEC), the most common causative agent of UTI, create an urgent need for vaccine development. Intranasal immunization of mice with UPEC outer membrane iron receptors FyuA, Hma, IreA, and IutA, conjugated to cholera toxin, provides protection in the bladder or kidneys under conditions of challenge with UPEC strain CFT073 or strain 536. On the basis of these data, we sought to optimize the vaccination route (intramuscular, intranasal, or subcutaneous) in combination with adjuvants suitable for human use, including aluminum hydroxide gel (alum), monophosphoryl lipid A (MPLA), unmethylated CpG synthetic oligodeoxynucleotides (CpG), polyinosinic:polycytidylic acid (polyIC), and mutated heat-labile E. coli enterotoxin (dmLT). Mice intranasally vaccinated with dmLT-IutA and dmLT-Hma displayed significant reductions in bladder colonization (86-fold and 32-fold, respectively), with 40% to 42% of mice having no detectable CFU. Intranasal vaccination of mice with CpG-IutA and polyIC-IutA significantly reduced kidney colonization (131-fold) and urine CFU (22-fold), respectively. dmLT generated the most consistently robust antibody response in intranasally immunized mice, while MPLA and alum produced greater concentrations of antigen-specific serum IgG with intramuscular immunization. On the basis of these results, we conclude that intranasal administration of Hma or IutA formulated with dmLT adjuvant provides the greatest protection from UPEC UTI. This report advances our progress toward a vaccine against uncomplicated UTI, which will significantly improve the quality of life for women burdened by recurrent UTI and enable better antibiotic stewardship.” (Forsyth et al, no changes)

1.2. Main paper; discussion starts at 27:10 minutes

The Most Interesting Things (according to students)

The study emphasizes a unique interaction between fungus (Rhizopus microsporus), bacteria (Mycetohabitans), and viruses (narnaviruses), showcasing how all three influence fungal reproduction. Narnaviruses, as well as bacterial symbionts, are essential for successful sexual reproduction in fungi, showing an unexpected role for viruses in the life cycle of the fungus.

This article is not licensed for Creative Commons use; see the article’s copyright information. Thus, the abstract and figures cannot be copied here. 

2. Vision and Change Core Concepts and 2024 ASM Fundamental Statements

Snippet Main
Vision and Change Topics
  • Structure and Function (V&C_SF)
  • Impact of microorganisms (V&C_IM)
  • Evolution Evolution (V&C_E)
  • Microbial Ecology (V&C_ME)
ASM Fundamental Statements
  • Fundamental Statement 5 (ASM_5): The structure and function of microbes are revealed by the use of microscopy, culture, and metabolic analyses, molecular methods, and bioinformatic tools.
  • Fundamental Statement 6  (ASM_6): The distinct structures and processes in microbes can be targets for interspecies competition, antimicrobial treatments, and host immunity.
  • Fundamental Statement 28 (ASM_28): A minority of microbes are pathogens that can cause diseases and harm host organisms, society, and ecosystems.
  • Fundamental Statement 29 (ASM_29): The extent of microbial damage can be minimized by host-derived and external factors, including the microbiome, antibiotics, and immunity.
  • Fundamental Statement 3 (ASM_3): The evolution of microbes is impacted by their interactions with the environment and a variety of ecological forces, including other microbes, humans, and habitats.
  • Fundamental Statement 20 (ASM_20): Microbes are ubiquitous, found in diverse and dynamic ecosystems, where they use available resources and often form complex communities.

3.  Potential Learning Objectives for the Podcast

The student will be able to: Paper1 Order2
  • Identify how vaccine efficacy was quantified for this study.
  • Recall which factors affected vaccination success in generating a protective immune.
  • Recall why the vaccine antigen was specific for the urinary tract environment.
 S L
  • Assess antibody levels to make conclusions about the best immunization response.
 S H
  • Define the different routes of symbiont transmission.
  • Recall features of narnaviruses.
 M L
  • Evaluate how fungal variants in symbiotic transmission could affect fungal processes.
 M H

1 Papers: Snippet (S) or Main (M)

2 Learning Objectives: Lower Order or Higher Order (H)

4. Techniques Described (with Time Stamps)

Here is a link to a bio-dictionary that has many, but not all definitions if you need a definition: Explore Biology Bio-Dictionary

4.1. Snippet Paper

  • Vaccination Routes (9:47–18:05): Vaccines can perform differently when the route of administering the vaccine is different.  Here, the researchers tested different delivery methods for developing this vaccine, such as intramuscular, intranasal, and subcutaneous.
  • Bacteria Quantification (10:30–20:04): There are a number of ways to quantify bacterial growth including optical density and colony counts.  Here, the researchers measuring the levels of E. coli colonization in organs (CFU counts) post-vaccination via different routes and with different antigen/adjuvant combinations to assess vaccine protection.
  • Humoral Response (12:00–14:00): Enzyme Linked Immunosorbent Assays (ELISA) are assays used to detect either antibodies or antigens.  Here, mice were vaccinated with various antigens and adjuvant combinations, and then challenged by injecting bacteria. The humoral immune response was assessed by measuring antigen-specific serum IgG levels.

4.2. Main Paper

  • RNA Sequencing (30:30–end): This is a method of sequencing all of the RNA in a sample, which is also called transcriptomics.  Here, the researchers used the RNA sequences to find  viruses.
  • Symbiont Curing and Reconstitution (38:02–43:13): These are methods of removing and re-administering endosymbionts to a host. Researchers eliminated narnaviruses and bacterial endosymbionts from Rhizopus microsporus using antiviral and antibiotic treatments. Then, the bacteria will be reintroduced to assess the individual and combined effects of these symbionts on the fungus’ biology.
  • Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) (38:21–41:04):  This is a method that quantifies the amount of RNA for a particular gene by using a RNA dependent DNA polymerase (reverse transcriptase) combined with polymerase chain reaction (RT-PCR).  It is often used as a confirmation assay for RNA sequencing data.  This method was utilized to measure the abundance of narnavirus RNA in different fungal developmental stages and in the presence or absence of bacterial symbionts, providing insights into viral replication dynamics and transmission.

5. Connections to General Microbiology Processes/Concepts (with Time Stamps)

5.1. Snippet Paper

  • Immune Response Induction (2:47–9:41): Stimulating protective immunity using optimized vaccine formulations and adjuvants.
  • Pathogen Challenge (3:11–8:10): Exposing vaccinated subjects to UPEC to evaluate vaccine efficacy in preventing colonization.

5.2. Main Paper

  • Vertical Transmission of Narnaviruses (28:11–32:56 ): Exploring how narnaviruses are passed down through fungal asexual and sexual reproduction, ensuring their persistence within fungal populations across generations.
  • Symbiotic Interactions (36:06–38:21): Investigating the complex relationships between Rhizopus microsporus, its bacterial symbiont (Mycetohabitans), and narnaviruses, showing how these interactions impact the development and function of this fungus.

6. Podcast Questions

  1.  How is vaccine efficacy against urinary tract infection (UTI) assessed? [Pick all that apply]
    1. Measuring antigen-specific antibody levels in serum.
    2. Measuring total antibody and cytokine levels in serum.
    3. Measuring bacterial counts in the kidney and bladder.
    4. Measuring symptomatic compared to asymptomatic.

  2. What factors affected vaccine efficacy in this study? [Pick all that apply]

    1. Administration route
    2. Type of needle used
    3. Type of adjuvant used
    4. Choice of antigen
  3. Why were iron receptor proteins chosen as antigens for vaccines against UTI?
    1. Iron binding proteins are a necessity in the poor nutrient environment of the urinary tract..
    2. Iron is plentiful in the urinary tract to these proteins would be very highly expressed there.
    3. These siderophore proteins are highly antigenic and can promote a good immune response.
    4. Iron is known to promote biofilm formation and is necessary for establishing urinary infections.
  4. If three UTI vaccines (A, B, C) were tested and serum antibodies were assayed (table), which vaccine would you say is best?  Here, antibody binding is measured as the most diluted sample that still gives a positive signal.
Vaccine UTI specific antigen binding non-specific antigen binding
A 1:15000 Dilution 1:1300 Dilution
B 1:2400 Dilution 1:1285 Dilution
C 1:30000 Dilution 1:1325 Dilution
    1. Vaccine A because it gives a positive signal with a 1:150000 dilution.
    2. Vaccine B because it gives a response using the smallest dilution level.
    3. Vaccine C because it gives a positive signal with the highest dilution.
    4. None would be effective for immunization as all have non-specific binding.
  1. A vertically transmitted endosymbiont is _______ while a horizontally transmitted endosymbiont is _________.
    1. replicated within host tissues; exchanged during reproduction
    2. passed from parent to offspring; acquired from the environment
    3. produced during cellular division; transferred through direct contact
    4. inherited through genetic mutation; spread via host migration
  2. What is unusual about narnaviruses? [Pick all that apply]
    1. They are made of naked RNA (no capsid).
    2. They encode only a single, large protein.
    3. They have a large and complex genome.
    4. They can be at 10,000 copies in a cell.
  3. These studies on the three-way endosymbiotic relationship between the fungus, bacterium, and narnavirus indicate that all three contribute to fungal success.  If the fungus acquired a natural spontaneous mutation that destroyed the entry receptor for the narnaviruses, what would be the most likely outcome for that strain?
    1. Cell wall formation would increase.
    2. Spore formation would increase.
    3. DNA replication would decrease.
    4. Sexual reproduction would decrease.

7. Figure Reading Exercises

The following are two figure reading exercises, one from the snippet paper (Table 1) and one from the main paper (Figure 1).

7.1. First Figure Reading Exercise

7.1.1. Learning Objectives

Students will be able to: 

  • Identify key features of the tabular data.
  • Evaluate the data to make conclusions which antigen-adjuvant combinations and delivery routes were most effective at reducing bacterial burdens in specific tissues/fluids.

Experimental Background (Forsyth et al., Table 1)

Uninary tract infections (UTI) are common, affecting half of women over their lifetime. Additionally, there is concern that the main causative agent, uropathogenic Escherichia coli (UPEC) may develop resistance to common antibiotics.  To address these concerns Forsyth et al. (2020) conducted experiments for vaccine development for this common pathogen.  They conducted 35 immunization trials using three different delivery routes (column 1): intramuscular, intranasal, and subcutaneous.  They also tested vaccination efficacy using different adjuvants (column 3) and antigens (column 4).  In each case, either an adjuvant only (column 5) or a combination of adjuvant and antigen (column 6) was used. To quantify vaccination success, bacterial counts in urine, bladder, spleen, and kidneys (column 1 sample source) were determined using a plate count assay, which is reported as colony forming units (CFU).  Additionally, fold change between adjuvant and adjuvant + antigen (column 7) and statistical significance (column 8) were calculated.

This table was modified from the original table to be taller than wide to fit the book.  All data are present and footnotes have been adjusted to fit this format.

“TABLE 1 Median fold change in CFU in the urine, bladder, and kidneys of immunized mice.”

Sample a Route b Adjuvant c Antigen d Median_Adj e Median_Adj+Ag f FC g P h
Urine IM Alum Hma 1,840 105300 0.02 0.0257
Urine IM Alum IreA 1,840 7,285 0.25 0.0664
Urine IM PolyIC Hma 23,100 734,500 0.03 0.4973
Urine IM PolyIC IreA 23,100 106,000 0.22 0.6421
Urine IM MPLA Hma 105,350 562,500 0.19 0.4813
Urine IM MPLA IreA 105,350 17,100 6.16 0.2466
Urine IM dmLT Hma 218,500 101,100 2.16 0.344
Urine IM dmLT IreA 218,500 36,500 5.99 0.1127
Urine IN PolyIC Hma 10,950 3,500 3.13 0.2409
Urine IN PolyIC IreA 10,950 4,845 2.26 0.4122
Urine IN PolyIC FyuA 284,000 54,100 5.25 0.3097
Urine IN PolyIC IutA 1,440,000 66,700 21.59 0.0599
Urine IN dmLT Hma 2,790 100 27.9 0.0693
Urine IN dmLT IreA 2,790 105 26.57 0.3674
Urine IN dmLT FyuA 210,450 5,605 37.55 0.0825
Urine IN dmLT IutA 16,400 619 26.49 0.1866
Urine IN CpG Hma 97,050 9,285 10.45 0.4332
Urine IN CpG IreA 97,050 8,215 11.81 0.4944
Urine IN CpG FyuA 7,910 961 8.23 0.6403
Urine IN CpG IutA 44,530 1,240 35.91 0.1959
Urine SQ Alum Hma 2,218 100 22.18 0.1246
Urine SQ Alum IreA 2,218 3,165 0.7 0.7828
Urine SQ PolyIC Hma 100 1,705 0.06 0.7168
Urine SQ PolyIC IreA 100 1,710 0.06 0.5473
Urine SQ dmLT Hma 119,000 8,955 13.29 0.3154
Urine SQ dmLT IreA 119,000 213,500 0.56 0.9048
Urine SQ MPLA Hma 31,900 232,600 0.14 0.7988
Urine SQ MPLA IreA 31,900 202,000 0.16 0.4002
Bladder IM Alum Hma 100 8670 0.01 0.2628
Bladder IM Alum IreA 100 2,950 0.03 0.9709
Bladder IM PolyIC Hma 6,735 37,350 0.18 0.0522
Bladder IM PolyIC IreA 6,735 13,550 0.5 0.5326
Bladder IM MPLA Hma 100 4,810 0.02 0.3285
Bladder IM MPLA IreA 100 1,690 0.06 0.7799
Bladder IM dmLT Hma 28,200 92,650 0.3 0.4311
Bladder IM dmLT IreA 28,200 14,500 1.94 0.7275
Bladder IN PolyIC Hma 14,600 6,355 2.3 0.1009
Bladder IN PolyIC IreA 14,600 3,330 4.38 0.1457
Bladder IN PolyIC FyuA 5,500 11,800 0.47 0.5941
Bladder IN PolyIC IutA 50,900 11,800 4.31 0.1469
Bladder IN dmLT Hma 3,205 100 32.05 0.024
Bladder IN dmLT IreA 3,205 3,170 1.01 0.902
Bladder IN dmLT FyuA 2,955 2,835 1.04 0.4233
Bladder IN dmLT IutA 8,610 100 86.1 0.0181
Bladder IN CpG Hma 19,350 5,755 3.36 0.1321
Bladder IN CpG IreA 19,350 3,035 6.38 0.0608
Bladder IN CpG FyuA 3,130 5,625 0.56 0.855
Bladder IN CpG IutA 5,255 8,570 0.61 0.7791
Bladder SQ Alum Hma 3,240 8,205 0.39 0.794
Bladder SQ Alum IreA 3,240 4,655 0.7 0.9271
Bladder SQ PolyIC Hma 1,505 14,650 0.1 0.0052
Bladder SQ PolyIC IreA 1,505 4,410 0.34 0.2559
Bladder SQ dmLT Hma 2,750 2,555 1.08 0.9478
Bladder SQ dmLT IreA 2,750 11,360 0.24 0.7122
Bladder SQ MPLA Hma 5,240 13,800 0.38 0.5935
Bladder SQ MPLA IreA 5,240 14,700 0.36 0.081
Kidney IN Alum Hma 10,940 6,860 1.59 0.9861
Kidney IM Alum IreA 10,940 10,045 1.09 0.5761
Kidney IM PolyIC Hma 9,650 3,975 2.43 0.2834
Kidney IM PolyIC IreA 9,650 750 12.87 0.1808
Kidney IM MPLA Hma 3,455 13,620 0.25 0.3888
Kidney IM MPLA IreA 3,455 470 7.35 0.8994
Kidney IM dmLT Hma 40,400 6,650 6.08 0.24
Kidney IM dmLT IreA 40,400 11,000 3.67 0.7252
Kidney IN PolyIC Hma 1,409 1,810 0.78 0.9999
Kidney IN PolyIC IreA 1,409 5,125 0.27 0.7937
Kidney IN PolyIC FyuA 1,180 927 1.27 0.9999
Kidney IN PolyIC IutA 640 1,600 0.4 0.5804
Kidney IN dmLT Hma 407 542 0.75 0.6033
Kidney IN dmLT IreA 407 1,340 0.3 0.7087
Kidney IN dmLT FyuA 387 3,159 0.12 0.0476
Kidney IN dmLT IutA 4,950 1,130 4.38 0.2536
Kidney IN CpG Hma 13,500 1,885 7.16 0.1419
Kidney IN CpG IreA 13,500 6,490 2.08 0.2991
Kidney IN CpG FyuA 312 773 0.4 0.833
Kidney IN CpG IutA 21,100 161 131.06 0.0462
Kidney SQ Alum Hma 198 100 1.98 0.2391
Kidney SQ Alum IreA 198 2,315 0.09 0.3376
Kidney SQ PolyIC Hma 100 100 1 0.4241
Kidney SQ PolyIC IreA 100 9,615 0.01 0.0274
Kidney SQ dmLT Hma 4,390 12,440 0.35 0.4422
Kidney SQ dmLT IreA 4,390 4,990 0.88 0.9675
Kidney SQ MPLA Hma 41,800 5,615 7.44 0.2818
Kidney SQ MPLA IreA 41,800 54,650 0.76 0.2309
a Sample: Urine, Bladder, Kidney
CFU when immunized with the adjuvant alone.
b Routes: Intramuscular (IM), Intranasal (IN), Subcutaneous (SQ)
c Adjuvants: aluminum hydroxide gel (Alum), polyinosinic:polycytidylic acid (PolyIC), monophosphoryl lipid A (MPLA), detoxified E. coli enterotoxin (dmLT), unmethylated CpG synthetic oligodeoxynucleotides (CpG)
d Antigens used are different proteins involved in iron-binding (Hma, IreA, FyuA, IutA)
e Median_Adj: Median CFU when immunized with the adjuvant alone.
f Median_Adj+Antigen: Median CFU when immunized with the adjuvant formulated with antigen
g FC: fold change in median CFU when immunized with the adjuvant alone compared to mice immunized with the adjuvant formulated with antigen. Fold changes greater than 2 are shown in bold.
h P value as determined by two-tailed Mann-Whitney test. Significant differences (<0.05) are shown in bold.

7.1.2. Questions

  1. How many different adjuvants were tested in this experiment?
    1. three
    2. four
    3. five
    4. six
  2. What P-value threshold indicates statistical significance in this table?
    1. Greater than 0.05
    2. Less than 0.05
    3. Equal to 0.05
    4. Any P value is significant
  3. What delivery route consistently showed significant reductions in bacterial presence across organs?
    1. Intranasal (IN)
    2. Intramuscular (IM)
    3. Subcutaneous (SQ)
    4. All routes were equal
  4. Which route-adjuvant-antigen combination shows the greatest reduction of bacterial burden in the bladder compared to adjuvant alone?
    1. Intranasal-dMLT-IutA
    2. Intranasal-dMLT-Hma
    3. Intranasal-CpG-IreA
    4. Intranasal-PolyIC-IreA
  5. Which route-adjuvant-antigen combination shows the greatest reduction of bacterial burden in the kidneys compared to adjuvant alone?
    1. Intranasal-CpG-IreA
    2. Intranasal-dMLT-IutA
    3. Intranasal-CpG-Hma
    4. Intranasal-CpG-IutA

7.2. Second Figure Reading Exercise 

7.2.1. Learning Objectives

Students will be able to:

  • Identify key features of bar charts, stacked bar charts, and phylogenetic tree visualizations.
  • Evaluate the data to draw conclusions about read mapping abundances per genome, organismal source of the narnaviruses, and evolutionary relatedness of viruses.

Experimental Background (Espino-Vasquez et al., Figure 1)

Fungal-bacterial symbiotic relationships are important in agriculture and public health.  One model of these interactions is between the fungus Rhizopus microsporus, and bacteria Burkholderia, recently renamed Mycetohabitans. In an effort to better characterize the relationships and metabolism features of this symbiotic relationship Espino-Vasquez et al. (2020) employed RNA sequencing of individual and mixed cultures of two fungal strains (813, 814) and two bacterial strains (B4 and B7).   They constructed a mixed reference genomic database with more than 40 fungal and bacterial species to identify the genes being expressed in these relationships.  Guanosine:Cytosine (GC) content differences are known hallmark features of different genomes, so the researchers mapped and quantified sequencing reads from strain 813 or 814 cultures by GC content and mapped genome: fungal genome (gray), bacterial genomes (black) or unmapped (white bars) (panel A).  Unmapped reads were investigated and determined to have similarity to two narnaviruses, so the reads in the libraries were mapped to Rhizosporus, Burkholderia, two narnaviruses, and RNA-dependent DNA polymerases, which are hallmark genes of these RNA viruses (panel B).  To identify the evolutionary/taxonomic relationship of these narnaviruses to other narnaviruses, they translated the narnavirus RNA-dependent RNA polymerase sequences (RdRp) and clustered them, along with others identified by BLASTp, to construct a phylogenetic tree (panel C).

  • Espino-Vasquez et al (2020) is not licensed for Creative Commons use, so the figure cannot be copied here.  Please see the article on the journal’s web page. 

7.2.2. Questions

  1. Which species’s mapped reads are noted by the color black in panel A?
    1. Burkholderia
    2. Rhizopus
    3. Unmapped
  2. What is the GC content of the most abundant reads (panel A, left graph)?
    1. 38
    2. 44
    3. 57
    4. 98
  3. Which genome’s mapped reads are noted by the “second to lightest gray” in panel B?
    1. Burkholderia
    2. Rhizopus
    3. RmVN-20S
    4. RmNV-23S
    5. RdRp
    6. Unmapped
  4. Which organism contributes the highest percentage of mapped reads from cultures of fungal strain 814 wt (panel B)?
    1. Burkholderia
    2. Rhizopus
    3. RmNV-20S
    4. RmNV-23S
  5. Based on these data, which fungal strain is the source of the narvaviruses? What is your evidence?
    1. Burkholderia; the narnavirus reads are only present when the bacteria are present.
    2. Rhizopus strain 813; the narnavirus reads are only present when this fungus is present.
    3. Rhizopus strain 814; the narnavirus reads are only present when this fungus is present.
    4. Both Rhizopus strains; the narnavirus reads are present when either fungi is present.
  6. What does a phylogenetic tree, like that shown in panel C, allow us to visualize?
    1. The distribution of GC content among sequences; it infers horizontal gene transfer.
    2. The proportion of reads mapped to unmapped regions; it indicates mapping success.
    3. The presence of fungal-bacterial RNA interactions; it infers a shared metabolism.
    4. The similarities and differences among sequences; it infers evolutionary relatedness.
  7. Based on the phylogenetic tree (panel C), which viral RdRp is most related to the Rhizopus microsporus 20S narnavirus RdRp found in this study?
    1. Aedes angustivittatus narnavirus
    2. Rhizopus microsporus 23S RNA narnavirus
    3. Saccharomyces 20S RNA narnavirus
    4. Saccharomyces 23S RNA narnavirus
  8. Based on the phylogenetic tree (panel C), which viral group’s RdRp are most related to the narnavirus RdRp?  What is your evidence?
    1. Ourmiavirus
    2. Mitovirus
    3. Leviviridae
    4. We can’t tell from these data.

8. Paper Information and Licensing

8.1. Snippet paper

  • Forsyth VS, Himpsl SD, Smith SN, Sarkissian CA, Mike LA, Stocki JA, Sintsova A, Alteri CJ, Mobley HLT. 2020. Optimization of an Experimental Vaccine To Prevent Escherichia coli Urinary Tract Infection. mBio. 11(2):e00555-20. doi: 10.1128/mbio.00555-20
  • This article is licensed for Creative Commons use using CC BY 4.0, which allows re-use and adaptation with proper attribution and notation of any changes.

8.2. Main paper

  • Espino-Vázquez AN, Bermúdez-Barrientos JR, Cabrera-Rangel JF, Córdova-López G, Cardoso-Martínez F, Martínez-Vázquez A, Camarena-Pozos DA, Mondo SJ, Pawlowska TE, Abreu-Goodger C, Partida-Martínez LP. 2020. Narnaviruses: novel players in fungal-bacterial symbioses. ISME J.14(7):1743-1754. doi: 10.1038/s41396-020-0638-y.
  • This article is not licensed for Creative Commons use; see the article’s copyright information. Thus, the abstract and figures cannot be copied here.

License

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Podcast Annotation and Resources in Microbiology Copyright © 2025 by Rebecca Seipelt-Thiemann; Nancy Boury; Gwendowlyn S. Knapp; Amaya Garcia Costas; and Patrick Armstrong is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

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