Molecular Typing of Campylobacter jejuni diarrheal isolates in a Hospital in Makokou, Gabon by Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR).
This article has been Reviewed by the following groups
Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
2. Abstract Context Campylobacter jejuni is responsible for 80% of the cases of human foodborne bacterial enteric infections worldwide. However, limited data on its genetic diversity exist, especially using the Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR). The aim of this study was to determine the genetic diversity of Campylobacter jejuni strains isolated from infant diarrheal feces at the Omar Bongo Ondimba Regional Health Center of Makokou (CHROBOM), Gabon. Material and methods 58 strains of Campylobacter jejuni from patients with gastroenteritis were used for this work. The ERIC-PCR method was used to characterize genetic diversity. The binomial manual method via the online analysis system (http://insilico.ehu.es/dice_upgma/) was used to establish the dendrogram and calculate the discriminatory power of the Simpson diversity index (D). Results The genotyping of Campylobacter jejuni isolates by the ERIC-PCR method revealed a discriminatory index D=0.8451, dividing the 58 isolates into 10 clusters, with 33 genotypic profiles, including 22 non-repeated profiles and 11 repeated profiles. These results indicate a rather polymorphic diversity of Campylobacter jejuni in the Makokou region of Gabon. Conclusion The high discriminatory diversity index obtained in this study demonstrates the polymorphic richness within Campylobacter jejuni strains as revealed by the ERIC-PCR method.
Article activity feed
-
Thanks for addressing the comments raised by the reviewers and myself.
-
-
This study would be a valuable contribution to the existing literature. This is a study that would be of interest to the field and community. The reviewers have highlighted major concerns with the work presented. Please ensure that you address their comments. Having received reviewer comments, it is clear the work requires additional experimental work. The size of the study is too small. How do you know for sure that all isolates are C. jejuni? Some other mean of identification needs to be included. Just the pattern seems too little to gain any meaningful insights from them. How do your results compare to other studies? Have these band patterns been observed in other studies using ERIC-PCR too? Do you have information of the patients and how they were treated and with what? Can you match this to the clusters?
-
Comments to Author
The authors describe the diversity of Campylobacter jejuni isolated from stools of 58 children hospitalized for diarrhea in Gabon. In order to differentiate the strains and obtain a measure of their diversity as well as possible epidemiological information, they use a very simple and relatively cheap method, ERIC-PCR. It is interesting, because it confirms results of very many previous studies proving that the sources of campyclobacters causing diarrheal disease are very diverse. However, there are several points which need additional care. Major: 1. About 10% of strains did not amplify in the PCR under the conditions used: the authors should try to improve their protocol (quantity and quality of input DNA, amplification conditions, primers etc.) to obtain a more uniform ERIC-PCR-product (there …
Comments to Author
The authors describe the diversity of Campylobacter jejuni isolated from stools of 58 children hospitalized for diarrhea in Gabon. In order to differentiate the strains and obtain a measure of their diversity as well as possible epidemiological information, they use a very simple and relatively cheap method, ERIC-PCR. It is interesting, because it confirms results of very many previous studies proving that the sources of campyclobacters causing diarrheal disease are very diverse. However, there are several points which need additional care. Major: 1. About 10% of strains did not amplify in the PCR under the conditions used: the authors should try to improve their protocol (quantity and quality of input DNA, amplification conditions, primers etc.) to obtain a more uniform ERIC-PCR-product (there are quite a few papers describing ERIC-PCT for C. jejuni) 2. The amounts of DNA shown in Figure 1 vary widely - the authors should measure DNA present in the amplification reaction and standardize the quantities used for the gel. 3. The authors should avoid having genomic DNA in the amplification product (DNA failing to enter the gel, as in 23, 36, and 49/53 to a lesser extent) 4. The relation between C-numbers (Figure 1 and 2) and E-profile-numbers in Table 3 are unclear. Where do C25/27 C48/50 and C57/58 belong - identical in Figure 1. Minor: 1. The paper does not need details on calculation discriminatory power; just giving Simpsons index of diversity is sufficient 2. The C-numbers in red on the graph are almost impossible to read. List the m from left to right in the legend 3. The colours in Figure 2 can not readily be distinguished and the numbers can be barely seen
Please rate the manuscript for methodological rigour
Poor
Please rate the quality of the presentation and structure of the manuscript
Poor
To what extent are the conclusions supported by the data?
Partially support
Do you have any concerns of possible image manipulation, plagiarism or any other unethical practices?
No
Is there a potential financial or other conflict of interest between yourself and the author(s)?
No
If this manuscript involves human and/or animal work, have the subjects been treated in an ethical manner and the authors complied with the appropriate guidelines?
Yes
-
Comments to Author
Dear Author's, Please check the comments below that need to be considered during your improvement of the MS. Best wishes Lines 39, 42, 44 - I suggest abbreviating Campylobacter jejuni to C.jejuni. Line 39 - Isolates should not be italicized Line 39, Results - Has a similarity profile emerged that suggests a common source epidemic etc.? Lines 51, 51 - please consider the other species, which cases? Line2 61-66 - Have you interpreted the molecular method here in comparison with AMR analysis? Have you performed AMR testing on the isolates? Line2 80-85 - If we compare it with these methods, we should not praise it too much, it can only be a simple alternative in laboratories where these are not available. Line 88, reference 11 - If you intend ERIC-PCR give more citations such as; …
Comments to Author
Dear Author's, Please check the comments below that need to be considered during your improvement of the MS. Best wishes Lines 39, 42, 44 - I suggest abbreviating Campylobacter jejuni to C.jejuni. Line 39 - Isolates should not be italicized Line 39, Results - Has a similarity profile emerged that suggests a common source epidemic etc.? Lines 51, 51 - please consider the other species, which cases? Line2 61-66 - Have you interpreted the molecular method here in comparison with AMR analysis? Have you performed AMR testing on the isolates? Line2 80-85 - If we compare it with these methods, we should not praise it too much, it can only be a simple alternative in laboratories where these are not available. Line 88, reference 11 - If you intend ERIC-PCR give more citations such as; https://doi.org/10.1111/jfs.13161 Line 94 , Bacterial Strains: - How did you diagnose C. jejuni? In relation to these: - you need to provide a method of isolation and preliminary identification - You need to add a confirmatory method such as API, species-specific PCR or sequencing Line2 97-99 - Were there any variations in sample origins that ERIC-PCR could categorize? Line 103 - "young colonies" - It is not a widely accepted expression, instead it can be said that ??? solid medium and fresh culture obtained as a result of ??? incubations were used. Line 103 - I suggest changing "the genome" to "total DNA" Line 103 - I suggest changing "strains of Campylobacter jejuni " to "C.jejuni strains" Lines 106-108 -ERIC-PCR references need to be multiple (such as Versalovic, Koeuth, and Lupskil), please check. Line 144 - "amplified fragments" in Figure ? Lines 147-148 (figure 1 legend) - What is the purpose of using a positive control against the amplification target of ERIC-PCR? Did you compare the profiles of the positive control and field strains in your findings and discussion? What did you find? How did you interpret it? Line 151 - "C17, C20 and C47" - The coding of the strains is mentioned for the first time, shouldn't these be written in the material section at the beginning? Lines 152-155 - "The most common bands were those of 1200, 800 and 153 700pb in size. The least frequent were bands greater than 1500bp in size and those with 1500,154 1300, 1000, 900, 750, 650, 600, 500, 400, 350, and 300pb" there's not much point in writing this Lines 154-155: - what could be the cause, - The problem of DNA presence, integrity and quality may come to mind, or you will have to discuss the reason for the failure of ERIC-PCR to amplify - Instead, it can be said that we started with 52 amplified strains. - it's your choice Line 157, Table 1 - There is no need for such a table, the dendrogram contains almost all this information. Lines 160-161 - Since you wrote it as text, there is no need for such a simple table (Table 2), because it is repetitive. Line 163, Figure 2: - especially the resolution of isolate codes should be increased, it is not visible as it is - What was the similarity index score, the reason should be explained - What does it mean by color, locations?, information about this subject should be given in the method section - It would be great if the demographic characteristics of the donors, virulence factors of the strains and AMR profiles were added, if any. Line 163 - "origin of patients" - these origins should be stated in material section Line 168, Table 3: - It is not clear which profile the cluster corresponds to - locations can also be added to the table, if there will be no repetition of the balance program Lines 171-173 - homogeneity and heterogeneity of clusters should be further elaborated Line 183 - "chicken shreds and feces" - The host is different, it must first be compared with infants Lines 185-186 - yet the mansions from which they were obtained are different, this is a stronger possibility Line 223, Conclusion - a general conclusion is presented, it should be rewritten by highlighting the potential/deficiencies of the core findings of your study
Please rate the manuscript for methodological rigour
Poor
Please rate the quality of the presentation and structure of the manuscript
Satisfactory
To what extent are the conclusions supported by the data?
Partially support
Do you have any concerns of possible image manipulation, plagiarism or any other unethical practices?
No
Is there a potential financial or other conflict of interest between yourself and the author(s)?
No
If this manuscript involves human and/or animal work, have the subjects been treated in an ethical manner and the authors complied with the appropriate guidelines?
Yes
-