Mar 29, 2024

Public workspaceMetabarcoding Fecal Swabs or Stomach Contents for Fish and Crustaceans using 2-PCR protocol and Illumina MiSeq V.1

  • 1University of Arizona
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Protocol CitationEldridge Wisely 2024. Metabarcoding Fecal Swabs or Stomach Contents for Fish and Crustaceans using 2-PCR protocol and Illumina MiSeq. protocols.io https://dx.doi.org/10.17504/protocols.io.ewov1qxokgr2/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License,  which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: November 19, 2023
Last Modified: March 29, 2024
Protocol Integer ID: 91145
Abstract
This protocol describes a method to metabarcode a 170bp region of the mitochondrial16S rRNA gene of crustaceans and a 163-185bp region of the mitochondrial 12S rRNA gene of fishes. These regions are subjected to PCR separately in multiple replicates and the resulting PCR products are pooled by sample and then indexed for sequencing on an Illumina MiSeq platform.
Image Attribution
Haley Capone
Guidelines
The PCR conditions described here are different from the PCR conditions described by Miya et al., and Berry et al. in their respective publications introducing the primers used here. This difference is due to the use of the Takara High Fidelity PCR EcoDry Premix in this protocol.
Materials
96-well PCR plates
Adhesive foil PCR plate covers

1.5mL tubes

Glenn et al. Adapterama I iNext indexing primers A-H and 1-12.

PCR machine

Equipment to run gels
optionally: equipment for fluorometric quantification


Protocol materials
ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14
ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14
ReagentMiFish-FIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
ReagentMiFish-RIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
ReagentCrustacean16S-FIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
ReagentCrustacean16S-RIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
ReagentCrustacean16S-FIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
ReagentCrustacean16S-RIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14
ReagentTakara High Fidelity PCR EcoDry PremixTakara Bio Inc.Catalog #639280
ReagentTakara High Fidelity PCR EcoDry PremixTakara Bio Inc.Catalog #639280
ReagentAgencourt AMPure XPBeckman CoulterCatalog #A63880
ReagentBuffer EBQiagenCatalog #19086
Reagent2x Kapa HiFi Hotstart Readymix Kapa BiosystemsCatalog #KK2602
ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14
ReagentBuffer EBQiagenCatalog #19086
Before start
Work in a pre-PCR lab, as separated as possible from post-PCR products.

Clean work area with 10% bleach solution before beginning work for the day, then change gloves so that no bleach carryover to your samples or reactions occurs.
Prepare Primers
Prepare Primers
Order metabarcoding primers with diversity spacers and Illumina overhang sequences (Illumina, 2013):ReagentMiFish-FIntegrated DNA Technologies, Inc. (IDT)Catalog #custom (Miya et al., 2015):
TCGTCGGCAGCGTCAGATGTGTATAAGAGACAGNNNNGTCGGTAAAACTCGTGCCAGC
ReagentMiFish-RIntegrated DNA Technologies, Inc. (IDT)Catalog #custom (Miya et al., 2015): GTCTCGTGGGCTCGGAGATGTGTATAAGAGACAGNNNNCATAGTGGGGTATCTAATCCCAGTTTG

ReagentCrustacean16S-FIntegrated DNA Technologies, Inc. (IDT)Catalog #custom Berry et al., 2017): TCGTCGGCAGCGTCAGATGTGTATAAGAGACAGNNNGGGACGATAAGACCCTATA

ReagentCrustacean16S-RIntegrated DNA Technologies, Inc. (IDT)Catalog #custom (Berry et al., 2017): GTCTCGTGGGCTCGGAGATGTGTATAAGAGACAGNNNATTACGCTGTTATCCCTAAAG

We got ours from https://www.idtdna.com/ as custom oligos at 25nm scale, with standard desalting.



Reconstitute primers to Concentration100 micromolar (µM) stock solutions by adding Amount40 µL of ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14

Make Concentration5 micromolar (µM) working solutions of each primer by adding Amount95 µL of ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14 and Amount5 µL of primer stock solution for each Amount100 µL of primer that you intend to use within the next week or so.



Create Plate Map
Create Plate Map
Determine which sample will go into each well. This should be the same for each primer set and each replicate. Include at least one extraction control (you can combine aliquots of the extraction controls from each round of DNA extraction into one tube, and use that as your single extraction control), and include a PCR negative control for each plate of PCR. See example below of 21 samples, a field negative sample, a combined extraction control, and a PCR negative.
12345
A
Sample8_rep1
Sample16_rep1
Sample24_rep1
PCR neg_rep1
Sample8_rep2
B
Sample7_rep1
Sample15_rep1
Sample23_rep1
Ext Con_rep1
Sample7_rep2
C
Sample6_rep1
Sample14_rep1
Sample22_rep1
Field Neg_rep1
Sample6_rep2
D
Sample5_rep1
Sample13_rep1
Sample21_rep1
Sample29_rep1
Sample5_rep2
E
Sample4_rep1
Sample12_rep1
Sample20_rep1
Sample28_rep1
Sample4_rep2
F
Sample3_rep1
Sample11_rep1
Sample19_rep1
Sample27_rep1
Sample3_rep2
G
Sample2_rep1
Sample10_rep1
Sample18_rep1
Sample26_rep1
Sample2_rep2
H
Sample1_rep1
Sample9_rep1
Sample17_rep1
Sample25_rep1
Sample1_rep2
678910
A
PCR neg_rep2
Sample8_rep3
B
Ext Con_rep2
Sample7_rep3
C
Field Neg_rep2
Sample6_rep3
D
Sample5_rep3
E
Sample4_rep3
F
Sample3_rep3
G
Sample2_rep3
H
Sample1_rep3
1112
A
PCR neg_rep3
B
Ext Con_rep3
C
Field Neg_rep3
D
E
F
G
H

Do not mix sample types between invasively sampled methods (fecal swabs, or stomach contents) and non-invasively sampled methods (eDNA from water or sediment) in the same PCR procedure. And don't plan to sequence both types in the same sequencing run with the combinatorial indexing scheme used here. The potential for contamination of the lower quantity eDNA samples by the higher quantity fDNA samples is too high.
MiFish Takara PCR Recipe
MiFish Takara PCR Recipe
Add Amount24 µL of your MiFish metabarcoding mastermix to each well of ReagentTakara High Fidelity PCR EcoDry PremixTakara Bio Inc.Catalog #639280

Add Amount1 µL DNA extracted from stomach contents or fecal swabs.
Mix and stir together with pipette tip, swirling to make sure the liquid is in the bottom, and bringing any bubbles to the surface of each reaction.
Cap each row of reaction tightly before beginning any other PCR reaction in the same room.
MiFish Takara PCR Conditions
MiFish Takara PCR Conditions
Temperature95 °C for Duration00:01:00
35 cycles of:
Temperature95 °C for Duration00:00:30
Temperature66 °C forDuration00:01:00
followed by:
Temperature68 °C forDuration00:01:00
Hold at Temperature4 °C


3m 30s
Crustacean_16S Takara PCR Recipe
Crustacean_16S Takara PCR Recipe
Make your Crustacean_16S Mastermix:

For each PCR replicate of each sample you intend to process (+10% overage), mix:
Amount2 µL Concentration5 micromolar (µM) ReagentCrustacean16S-FIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
Amount2 µL Concentration5 micromolar (µM) ReagentCrustacean16S-RIntegrated DNA Technologies, Inc. (IDT)Catalog #custom
Amount20 µL ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14



For a full plate of 96 reactions, multiply 105.6*the per-sample volumes in the recipe to make the mastermix.


Add Amount24 µL of your Crustacean_16S metabarcoding mastermix to each well of ReagentTakara High Fidelity PCR EcoDry PremixTakara Bio Inc.Catalog #639280
Add Amount1 µL DNA extract


Mix and stir together with pipette tip, swirling to make sure the liquid is in the bottom, and bringing any bubbles to the surface of each reaction.
Cap each row of reaction tightly before beginning any other PCR reaction in the same room.
Crustacean_16S Takara PCR Conditions
Crustacean_16S Takara PCR Conditions
4m
4m
Temperature95 °C for Duration00:01:00
35 cycles of:
Temperature95 °C for Duration00:00:30
Temperature50 °C for Duration00:01:00
Temperature68 °C for Duration00:00:30
followed by:
Temperature68 °C for Duration00:01:00
then hold at Temperature4 °C

4m
Visualize PCR Products
Visualize PCR Products
Make a 1.7% to 2% agarose gel and run a representative sample of reactions on it to make sure the PCRs worked, producing bands in the 250-300bp range. Check some PCR negatives to see that they don't have bands. Be very careful opening the PCR plate wells at this point to avoid cross-contamination.
Prepare EtOH for bead cleanup, and bring beads to room temperature
Prepare EtOH for bead cleanup, and bring beads to room temperature
12m 30s
12m 30s
Get AmpureXP beads out of the refrigerator, and bring to room temp, swirl to mix occasionally, or use a rocking platform.
Make fresh 80% EtOH so that you will have at least Amount200 µL of EtOH per well of the combined plate.

Get 2 sterile DNAase/RNAse free 96-well PCR plates out of their packaging and immediately cover with adhesive foil.

UV clean the plates for Duration00:15:00

One plate will be for the bead-cleanup steps, and the other will be for the final, cleaned reactions.
15m
Perform a 1.5x bead cleanup with Ampure XP beads.
Perform a 1.5x bead cleanup with Ampure XP beads.
12m 30s
12m 30s
in the bead-cleanup plate, do the following steps for one 8-sample row of the plate at a time, pulling back the foil cover for each row after the previous one has been completed.



pipette mix Amount10 µL combined PCR product with Amount15 µL ReagentAgencourt AMPure XPBeckman CoulterCatalog #A63880 .

Incubate Duration00:05:00 at room temperature.
5m
After the Duration00:05:00 incubation, place 96-well plate on a
forDuration00:02:00 or until liquid is clear.

7m
remove and discard liquid from the row, being careful not to touch the beads with the pipette or to let the beads dry for more than 30 seconds.
Add Amount100 µL of 80%EtOH to each well of beads. Incubate at TemperatureRoom temperature for Duration00:00:30


30s
Remove the EtOH, then immediately add another Amount100 µL of 80% EtOH to the wells, incubate for Duration00:00:30 TemperatureRoom temperature .

30s
Remove ALL EtOH, and let the row of beads dry just enough to lose some shine but not enough to start cracking. This should be approximately Duration00:00:30 to Duration00:01:00 .

1m 30s
Remove the plate with cleaned beads from the magnetic plate, and add Amount30 µL of ReagentBuffer EBQiagenCatalog #19086
to each well of beads, pipette mixing each well thoroughly. Incubate Duration00:05:00 at TemperatureRoom temperature

5m
Place back on the magnetic rack for Duration00:01:00 until liquid is clear again.

1m
Roll back the foil on the final cleaned reactions plate for the appropriate row. Remove the Amount30 µL clear eluate from the bead-cleanup plate, and place in the appropriate wells of the final cleaned reactions plate. Immediately cover this cleaned PCR product with either 8-strip caps.

uncover the next row of samples for cleaning and Go to until all rows are cleaned.

Prepare Indexing PCR
Prepare Indexing PCR
Create an indexing plate map and make sure your chosen indexes (iNext indexes) are color balanced if you aren't doing full 96-well plates at one time.

12345
A
S8 iNextA-F + iNext1-R
S16 iNextA-F + iNext2-R
etc.
MiFishPCRneg iNextAF+4R
Crust..PCRneg iNextAF+5R
B
S7 iNextB-F + iNext1-R
S15 iNextB-F + iNext2-R
C
S6 iNextC-F + iNext1-R
S14 iNextC-F + iNext2-R
D
etc.
E
F
G
H
678910
A
B
C
D
E
F
G
H
1112
A
B
C
D
E
F
G
H

See: Glenn, Travis C., Roger A. Nilsen, Troy J. Kieran, Jon G. Sanders, Natalia J. Bayona-Vásquez, John W. Finger, Todd W. Pierson, et al. 2019. “Adapterama I: Universal Stubs and Primers for 384 Unique Dual-Indexed or 147,456 Combinatorially-Indexed Illumina Libraries (iTru & iNext).” PeerJ 2019 (10). https://doi.org/10.7717/peerj.7755. Supplemental file S10

Prepare working solutions of Concentration5 micromolar (µM) of each indexing primer you intend to use.

Indexing PCR Mastermix Recipe:
Amount6 µL Reagent2x Kapa HiFi Hotstart Readymix Kapa BiosystemsCatalog #KK2602
Amount2.1 µL ReagentNuclease-free waterIntegrated DNA Technologies, Inc. (IDT)Catalog #11-05-01-14
per sample.

Multiply by number of wells *10% as explained above, to create master mix.
In a new, clean 96-well plate (UV before use if possible and prepare in a pre-PCR space):
Add Amount8.1 µL Indexing Mastermix to each well that will be used and add Amount0.7 µL of the Concentration5 micromolar (µM) iNext forward indexed primer for each horizontal row of the plate (8 letters), and Amount0.7 µL Concentration5 micromolar (µM) of the iNext reverse indexed primer for each vertical column of the plate (12 numbers) according to the indexing plate map.

Take the prepared indexing reactions to the post-PCR space to add the cleaned PCR product.

In the post-PCR area, add 2.5uL of cleaned PCR 1 product to their associated wells from the indexing plate map.
Indexing PCR Conditions
Indexing PCR Conditions
Temperature95 °C Duration00:03:00
8 cycles of:
Temperature98 °C Duration00:00:20
Temperature65 °C Duration00:00:15
Temperature72 °C Duration00:01:00

then hold Temperature4 °C


4m 35s
Optional gel to check Indexing PCR
Optional gel to check Indexing PCR
Optional: visualize PCR products in a 1.7-2% gel. Bands should be around 350-400bp.
Combine and Clean all indexed samples from each plate
Combine and Clean all indexed samples from each plate
Combine 10uL of up to 70 indexed samples (library) into a single 1.5mL tube. If there are more than 70 samples, you will need another tube.
Multiply the volume of the pooled libraries in each tube by 0.9 to get the volume of Ampure XP beads needed to clean up the reactions.
Perform a 0.9x bead cleanup with Ampure XP beads
Perform a 0.9x bead cleanup with Ampure XP beads
28m
28m
In the 1.5mL tube of pooled libraries, add 0.9x volume of Ampure XP beads and pipette mix well. incubate TemperatureRoom temperature for Duration00:10:00

10m
Make enough fresh 80% EtOH to have 2x the total volume of the beads+library pool plus a bit extra.
Place 1.5mL tube into a magnetic rack
and incubate TemperatureRoom temperature for Duration00:05:00

5m
Discard liquid and add an equal or greater volume of 80% EtOH. Incubate TemperatureRoom temperature for Duration00:01:00

1m
Repeat the ethanol wash a second time Go to , then after the second 80% EtOH wash, remove all EtOH and dry the beads slightly (just until no longer wet-looking but not cracking either).

Resuspend beads with Amount100 µL ReagentBuffer EBQiagenCatalog #19086 by pipette mixing thoroughly. Incubate TemperatureRoom temperature Duration00:10:00

10m
Place 1.5 mL tube back on magnet rack and wait until liquid is clear, approximately Duration00:02:00

2m
remove 100uL of the clear eluate from the tube with beads while on the magnet and place in a new 1.5mL tube.
Quantify with Qubit Broad range and visualize in a gel, then send for sequencing on a lane of MiSeq.
Protocol references
Berry, Tina E., Sylvia K. Osterrieder, Dáithí C. Murray, Megan L. Coghlan, Anthony J. Richardson, Alicia K. Grealy, Michael Stat, Lars Bejder, and Michael Bunce. 2017. “DNA Metabarcoding for Diet Analysis and Biodiversity: A Case Study Using the Endangered Australian Sea Lion (Neophoca Cinerea).” Ecology and Evolution 7 (14): 5435–53. https://doi.org/10.1002/ece3.3123.

Miya, M., Y. Sato, T. Fukunaga, T. Sado, J. Y. Poulsen, K. Sato, T. Minamoto, et al. 2015. “MiFish, a Set of Universal PCR Primers for Metabarcoding Environmental DNA from Fishes: Detection of More than 230 Subtropical Marine Species.” Royal Society Open Science 2 (7): 150088. https://doi.org/10.1098/rsos.150088.

Glenn, Travis C., Roger A. Nilsen, Troy J. Kieran, Jon G. Sanders, Natalia J. Bayona-Vásquez, John W. Finger, Todd W. Pierson, et al. 2019. “Adapterama I: Universal Stubs and Primers for 384 Unique Dual-Indexed or 147,456 Combinatorially-Indexed Illumina Libraries (iTru & iNext).” PeerJ 2019 (10). https://doi.org/10.7717/peerj.7755.