Reviewer's report
Title:The Pancreatic Zymogen Granule Membrane Protein, GP2, Binds
Escherichia coli Type 1 Fimbriae
Version: 1Date:7 April 2009
Reviewer: Michael Rindler
Reviewer's report:
This manuscript describes the binding of E. coli to GP2. GP2 is pancreatic
protein that is shed into the pancreatic juice. It is a relative of uromodulin, whose
ability to bind to fimbriated bacteria is well established. Using in vitro microplate
binding assays and recombinant GP2 and purified uromodulin, the binding of
fimbriated bacteria to GP2 is confirmed. Moreover GP2 is shown to bind to type I
fimbriae through mannose residues in the oligosaccharide side chains and it also
is capable of binding variants in fimbriae sequence that are normally poor
substrates for uromodulin. The authors speculate that GP2 may play a role in
protecting the pancreatic duct and bile duct from infection, similar to that thought
to be played by uromodulin in the urinary system.
The experiments are well conceived and performed. The conclusions are sound.
The findings are novel and I have no major criticisms.
There is one minor revision that I consider reasonable if not essential:
1. Concerning Figure 5, it should be possible to give a quantitative estimate as to
the relative affinity for each protein for the bacteria if not the absolute affinity.
Also, it seems the KB91 binding is substantially lower than Nu14 for GP2,
perhaps even in the same relative range as the difference for uromodulin.
Therefore, it appears that the overall affinity for binding the bacteria is much
higher, but the relative binding to the M1L and M1H is the same between the two
proteins.
There are a number of minor discretionary revisions that would improve the
manuscript:
1. In the Methods Reagents section, the procedures for purification of
recombinant GP2 should be explained at least briefly. The reader should not
have to refer to previous papers to understand if full length GP2 or secreted GP2
was used and what method was used to purify it. The purity of the recombinant
GP2 is a critically important issue and deserves a few sentences of explanation.
2. In the Results section, what is the explanation for the antibody blocking the
binding to fimbriae? The fimbriae should theoretically bind to oligosaccharides
even when the antibody is bound.
3. In Figure 5 it is difficult to see the data points for Nu14-THP in the graph. They
should be changed to circles or some other symbol.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
Reviewer's report
Title:The Pancreatic Zymogen Granule Membrane Protein, GP2, Binds
Escherichia coli Type 1 Fimbriae
Version: 1Date:7 April 2009
Reviewer: Michael Rindler
Reviewer's report:
This manuscript describes the binding of E. coli to GP2. GP2 is pancreatic
protein that is shed into the pancreatic juice. It is a relative of uromodulin, whose
ability to bind to fimbriated bacteria is well established. Using in vitro microplate
binding assays and recombinant GP2 and purified uromodulin, the binding of
fimbriated bacteria to GP2 is confirmed. Moreover GP2 is shown to bind to type I
fimbriae through mannose residues in the oligosaccharide side chains and it also
is capable of binding variants in fimbriae sequence that are normally poor
substrates for uromodulin. The authors speculate that GP2 may play a role in
protecting the pancreatic duct and bile duct from infection, similar to that thought
to be played by uromodulin in the urinary system.
The experiments are well conceived and performed. The conclusions are sound.
The findings are novel and I have no major criticisms.
There is one minor revision that I consider reasonable if not essential:
1. Concerning Figure 5, it should be possible to give a quantitative estimate as to
the relative affinity for each protein for the bacteria if not the absolute affinity.
Also, it seems the KB91 binding is substantially lower than Nu14 for GP2,
perhaps even in the same relative range as the difference for uromodulin.
Therefore, it appears that the overall affinity for binding the bacteria is much
higher, but the relative binding to the M1L and M1H is the same between the two
proteins.
There are a number of minor discretionary revisions that would improve the
manuscript:
1. In the Methods Reagents section, the procedures for purification of
recombinant GP2 should be explained at least briefly. The reader should not
have to refer to previous papers to understand if full length GP2 or secreted GP2
was used and what method was used to purify it. The purity of the recombinant
GP2 is a critically important issue and deserves a few sentences of explanation.
2. In the Results section, what is the explanation for the antibody blocking the
binding to fimbriae? The fimbriae should theoretically bind to oligosaccharides
even when the antibody is bound.
3. In Figure 5 it is difficult to see the data points for Nu14-THP in the graph. They
should be changed to circles or some other symbol.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
Please review this paper.
user
Reviewer's report
Title:The Pancreatic Zymogen Granule Membrane Protein, GP2, Binds
Escherichia coli Type 1 Fimbriae
Version: 1Date:7 April 2009
Reviewer: Michael Rindler
Reviewer's report:
This manuscript describes the binding of E. coli to GP2. GP2 is pancreatic
protein that is shed into the pancreatic juice. It is a relative of uromodulin, whose
ability to bind to fimbriated bacteria is well established. Using in vitro microplate
binding assays and recombinant GP2 and purified uromodulin, the binding of
fimbriated bacteria to GP2 is confirmed. Moreover GP2 is shown to bind to type I
fimbriae through mannose residues in the oligosaccharide side chains and it also
is capable of binding variants in fimbriae sequence that are normally poor
substrates for uromodulin. The authors speculate that GP2 may play a role in
protecting the pancreatic duct and bile duct from infection, similar to that thought
to be played by uromodulin in the urinary system.
The experiments are well conceived and performed. The conclusions are sound.
The findings are novel and I have no major criticisms.
There is one minor revision that I consider reasonable if not essential:
1. Concerning Figure 5, it should be possible to give a quantitative estimate as to
the relative affinity for each protein for the bacteria if not the absolute affinity.
Also, it seems the KB91 binding is substantially lower than Nu14 for GP2,
perhaps even in the same relative range as the difference for uromodulin.
Therefore, it appears that the overall affinity for binding the bacteria is much
higher, but the relative binding to the M1L and M1H is the same between the two
proteins.
There are a number of minor discretionary revisions that would improve the
manuscript:
1. In the Methods Reagents section, the procedures for purification of
recombinant GP2 should be explained at least briefly. The reader should not
have to refer to previous papers to understand if full length GP2 or secreted GP2
was used and what method was used to purify it. The purity of the recombinant
GP2 is a critically important issue and deserves a few sentences of explanation.
2. In the Results section, what is the explanation for the antibody blocking the
binding to fimbriae? The fimbriae should theoretically bind to oligosaccharides
even when the antibody is bound.
3. In Figure 5 it is difficult to see the data points for Nu14-THP in the graph. They
should be changed to circles or some other symbol.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
assistant