Identification and Evaluation of the Salt and Acid—Alkaline Resistance of Rhizobium Species of Desmodium
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsMajor concerns
- Part 3.1 and 3.2 should be combined together.
- There are over 70 strains in line 163-165. But there are only 4 photos in Figure 2, which should be fully described in figure legend.
- The sequences used in Figure 3 should be deposited to GenBank and cited with accession numbers.
- Typical photos should be added for part 3.4.
- Details should be added as footnote in Table 1.
- The figures in page 9-11 should be rephrased according to author instruction.
- The PCA analysis should be carried out to evaluate factors.
Minor concerns
- The first character of ‘rhizobium’ should be in capital when it appears in italic around the whole manuscript.
- Figure number in part 3.5 should be corrected.
The language should be revised by native speakers.
Author Response
Reply to reviewers' comments
Manuscript ID: microbiolres-3529706
Type of manuscript: Article
Title: Identification and evaluation of the salt and acid‒alkaline
resistance of rhizobium species of Desmodium
Authors: Yunchi Zhu, An Hu, Xinyong Li, Lijuan Luo, Rongshu Dong *
Dear editor,
First of all, we would like to express our sincere thanks for your decision and your valuable comments and suggestions. Each of these comments is not only of great value to our revision in this manuscript but also helpful for us to further our understanding in the studying field. We have revised our manuscript point-by-point after carefully considering your comments. Here, we list below our responses to the comments/suggestions.
Please contact me if there are any other questions. Thank you very much for your help.
We are looking forward to hearing from you soon.
Sincerely yours,
Rongshu Dong, Ph. D
----------------------------------------------------------------------------------------------------------------------
Revised portions are marked in red in the manuscript and the responds to the reviewers’ comments point by point are as follows:
Reviewer #1: Major concerns
The comments are as follows:
Comment 1: Part 3.1 and 3.2 should be combined together.
Response 1: Thanks for the professional questions. Part 3.1 and 3.2 are combined together in our revised manuscript.
Comment 2: There are over 70 strains in line 163-165. But there are only 4 photos in Figure 2, which should be fully described in figure legend.
Response 2: Thanks for the professional questions.The figure legend is described in Figure 3 (Figure 2 of the original manuscript).
Comment 3:The sequences used in Figure 3 should be deposited to GenBank and cited with accession numbers.
Response 3: Thanks for the professional questions.The sequences with accession numbers are added in Figure 2 (Figure 3 of the original manuscript)
Comment 4:Typical photos should be added for part 3.4.
Response 4:Thanks for the professional questions. Figure 3. Effect of salt treatment on the growth of Desmodium rhizobia, which are added for part 3.4.
Comment 5:Details should be added as footnote in Table 1.
Response 5: Thanks for the professional questions. The footnote is added in Table 1.
Comment 6:The figures in page 9-11 should be rephrased according to author instruction.
Response 6: Thanks for the professional questions. Figure 4 and 5 are rephrased according to author instruction.
Comment 7:The PCA analysis should be carried out to evaluate factors.
Response 7: Thanks for the professional questions. In this study, the salt tolerance of strains was determined using solid and liquid media. Solid culture was used to qualitatively determine the effects of different salt (pH) treatments on the growth of strains, and liquid media was used to quantitatively determine the effects of salt (pH) on the growth of different strains through the determination of the OD600 values of the strains after incubation for up to 168 h. Growth curves of the strains were generated, and the salt tolerance ability of the strains was qualitatively and quantitatively determined. If the qualitative and quantitative salt tolerance abilities of the strains could be mutually verified and complemented each other, the test could only determine the OD600 value of a quantitative indicator, without the need to carry out principal component analysis to determine the salt tolerance or acid resistance of strains.
Comment 8:The first character of ‘rhizobium’ should be in capital when it appears in italic around the whole manuscript.
Response 8: Thanks for the professional questions. ‘rhizobium’ is revised to ‘Rhizobium’ on the whole manuscript.
Comment 9:Figure number in part 3.5 should be corrected.
Response 9: Thanks for the professional questions.‘Figure.3’ is revised to ‘Figure.4’.
Comment 10:However, there are several issues regarding nomenclature, data presentation and data interpretation, which the authors need to address to improve the readability and scientific rigor of this manuscript.
Response 10: Thanks for the professional questions. The readability and scientific rigor of this manuscript are revised according to reviewers' recommendations.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments and Suggestions for AuthorsIn this manuscript, the authors identified 62 strains of rhizobium from root nodules of four types of Desmodium by 16S rDNA sequencing, and performed salt tolerance and acid-base adaptability tests. This work bears significance in optimizing rhizobia inoculation in agricultural and environmental applications.
However, there are several issues regarding nomenclature, data presentation and data interpretation, which the authors need to address to improve the readability and scientific rigor of this manuscript.
- “Leech grass” is not a scientific nomenclature and therefore could induce confusion. Please replace this term with its binomial nomenclature.
- “Classification status” was used a couple of times in the manuscript, yet this term is ambiguous. Based on the context, this “status” refers to the slow- or fast-growing of the rhizobia strains based on 16S rRNA gene sequencing results. The authors should consider changing this term to a more informative one, for example, phylogenetic classification (of Desmodium rhizobia).
- The criteria by which the rhizobia are categorized as “slow-growing” or “fast-growing” should be clarified the first time this concept is discussed in the introduction (i.e., line 47-48).
- Line 38-39, “In our country” should be “In China”.
- The authors should be specific when referring to literatures in the manuscript. For example, references 16 and 17 are not quite relevant to the statement where they are referred to in line 52. Reference 16 reports effects of different rhizobium strains on nitrogen fixation of mung bean, and reference 17 discusses rhizobia inoculation of peanuts. While both references are about nitrogen fixation of rhizobia, they could not directly testify the generic variation of the interaction between rhizobia and Desmodium. The authors should elaborate on the references themselves and relate the conclusions of these references to the statement thewy are trying to make here, similar to what has been done on references 18 and 19.
- Line 100, “super-clean table” should be “clean bench” or “sterile bench”.
- Figure 2 needs a more informative figure caption. Which strain(s) of rhizobia is shown in this figure? What does this figure indicate? How to define fast-/slow-growing rhizobia based on this figure?
- Line 174, “Figure. 3” should be “Figure 3”.
- Line 211, “Figure 3” should be “Figure 4”.
- The displays of Figure 4 and Figure 5 need fixing regarding: 1) The axis titles are overlapped with the figure themselves; 2) the resolution of Figures 5 is too low.
- Line 181-195, are “group” and “class” the same concept here? If so please consider using consistent term throughout the manuscript to avoid confusion.
- The authors need to clarify what the “10 groups” are. Figure 3 shows only eight groups. Line 261-263 states only 9 groups even though line 260 states “…divided into 10 groups”. This inconsistency is confusing, and the authors need be more specific.
- Line 281-285. Here the conclusions indicate that fast-growing rhizobium strains dominate alkaline resistant strains (“9 of the 11 strains with high pH adaptability were fast-growing rhizobium 282 strains”) and slow-growing strains dominate acid resistant strains (“Among the 15 strains with strong acid resistance, 14 284 were slow-growing rhizobium strains”). But this is on the contrary to the conclusions shown in line 289-290 and line 301-303. The authors need to correct these statements to be consistent.
- Finally, the authors should discuss the significance of this work. How could the results generated be applicable to agricultural and environmental developments? Furthermore, the authors should discuss any possible future work. Since RM16 stands out with good salt resistance and acid-base adaptability, is there any future work about it? As shown in the Discussion section, there is probably a relationship between fast/slow-growing status of the strains and their acid-base adaptability, could this be further investigated by genomic sequencing and/or bio-functional assays?
Comments on the Quality of English Language
The authors should examine the manuscript and replace the non-scientific languages with professional nomenclatures.
Some examples have been included in the reviewer's comments above.
Author Response
Reply to reviewers' comments
Manuscript ID: microbiolres-3529706
Type of manuscript: Article
Title: Identification and evaluation of the salt and acid‒alkaline
resistance of rhizobium species of Desmodium
Authors: Yunchi Zhu, An Hu, Xinyong Li, Lijuan Luo, Rongshu Dong *
Dear editor,
First of all, we would like to express our sincere thanks for your decision and your valuable comments and suggestions. Each of these comments is not only of great value to our revision in this manuscript but also helpful for us to further our understanding in the studying field. We have revised our manuscript point-by-point after carefully considering your comments. Here, we list below our responses to the comments/suggestions.
Please contact me if there are any other questions. Thank you very much for your help.
We are looking forward to hearing from you soon.
Sincerely yours,
Rongshu Dong, Ph. D
----------------------------------------------------------------------------------------------------------------------
Revised portions are marked in red in the manuscript and the responds to the reviewers’ comments point by point are as follows:
Reviewer #2: Major concerns
The comments are as follows:
Comment 1: “Leech grass” is not a scientific nomenclature and therefore could induce confusion. Please replace this term with its binomial nomenclature.
Response 1:Thanks for the professional questions. “Leech grass” is revised to “pasturage” on the whole manuscript.
Comment 2:“Classification status” was used a couple of times in the manuscript, yet this term is ambiguous. Based on the context, this “status” refers to the slow- or fast-growing of the rhizobia strains based on 16S rRNA gene sequencing results. The authors should consider changing this term to a more informative one, for example, phylogenetic classification (of Desmodium rhizobia).
Response 2:Thanks for the professional questions.“Classification status” are revised to “phylogenetic classification ” on the whole manuscript.
Comment 3: The criteria by which the rhizobia are categorized as “slow-growing” or “fast-growing”should be clarified the first time this concept is discussed in the introduction (i.e., line 47-48).
Response 3:Thanks for the professional questions. The fast-growing rhizobia (strains can be grown at 3 to 5 d) ; slow-growing rhizobia (strains can be grown at 5 to 7 d) , which are added in the introduction section.
Comment 4: Line 38-39, “In our country” should be “In China”.
Response 4:Thanks for the professional questions.“In our country”is revised to“In China”.
Comment 5: The authors should be specific when referring to literatures in the manuscript. For example, references 16 and 17 are not quite relevant to the statement where they are referred to in line 52. Reference 16 reports effects of different rhizobium strains on nitrogen fixation of mung bean, and reference 17 discusses rhizobia inoculation of peanuts. While both references are about nitrogen fixation of rhizobia, they could not directly testify the generic variation of the interaction between rhizobia and Desmodium. The authors should elaborate on the references themselves and relate the conclusions of these references to the statement thewy are trying to make here, similar to what has been done on references 18 and 19.
Response 5: Thanks for the professional questions.The references 16 and 17 are replaced , which the topic of the interaction between rhizobia and Desmodium.
Comment 6: Line 100, “super-clean table” should be “clean bench” or “sterile bench”.
Response 6: Thanks for the professional questions.“super-clean table” is revised to “sterile bench”.
Comment 7: Figure 2 needs a more informative figure caption. Which strain(s) of rhizobia is shown in this figure? What does this figure indicate? How to define fast-/slow-growing rhizobia based on this figure?
Response 7: Thanks for the professional questions. The figure legend and note are described in Figure 3 (Figure 2 of the original manuscript).
Comment 8: Line 174, “Figure. 3” should be “Figure 3”.
Response 8: Thanks for the professional questions.“Figure. 3” is revised to “Figure 3”.
Comment 9: Line 211, “Figure 3” should be “Figure 4”.
Response 9: Thanks for the professional questions. “Figure 3” is revised to “Figure 4”.
Comment 10: The displays of Figure 4 and Figure 5 need fixing regarding: 1) The axis titles are overlapped with the figure themselves; 2) the resolution of Figures 5 is too low.
Response 10: Thanks for the professional questions.Figure 4 and 5 are rephrased according to author instruction.
Comment 11:Line 181-195, are “group” and “class” the same concept here? If so please consider using consistent term throughout the manuscript to avoid confusion.
Response 11: Thanks for the professional questions. “class” are revised to “group” throughout the manuscript.
Comment 12:The authors need to clarify what the “10 groups” are. Figure 3 shows only eight groups. Line 261-263 states only 9 groups even though line 260 states “…divided into 10 groups”. This inconsistency is confusing, and the authors need be more specific.
Response 12: Thanks for the professional questions. This problem are revised according to author instruction. The bacterial strains clustered into 8 groups on the phylogenetic tree. In some groups, there are two closely related strains. For example, Group 1 contains the similar strains *Bradyrhizobium huanghuaihaiense* and *Bradyrhizobium yuanmingense*, which together form the closest phylogenetic relationships with 10 strains. The 10 strains were Bradyrhizobium elkanii、Rhizobium oryzicola 、Bradyrhizobium huanghuaihaiense 、Rhizobium tropici 、 Rhizobium oryzicola、 Bradyrhizobium ganzhouense 、Bradyrhizobium centrosematis、 Bradyrhizobium pachyrhizi、Bradyrhizobium yuanmingense、Bradyrhizobium iriomotense.
Comment 13:Line 281-285. Here the conclusions indicate that fast-growing rhizobium strains dominate alkaline resistant strains (“9 of the 11 strains with high pH adaptability were fast-growing rhizobium 282 strains”) and slow-growing strains dominate acid resistant strains (“Among the 15 strains with strong acid resistance, 14 284 were slow-growing rhizobium strains”). But this is on the contrary to the conclusions shown in line 289-290 and line 301-303. The authors need to correct these statements to be consistent.
Response 13: Thanks for the professional questions. Thank you very much. This was caused by our carelessness when writing the manuscript.
“9 of the 11 strains with high pH adaptability were fast-growing Rhizobium strains, and 2 were slow-growing Rhizobium strains.” are revised to“9 of the 11 strains with high pH adaptability were slow-growing rhizobium strains, and 2 were fast-growing rhizobium strains”;
“fast-growing bacteria with strong acid resistance were dominant, and slow-growing bacteria with strong alkali resistance were dominant” are revised to “slow-growing bacteria with strong acid resistance were dominant, and fast-growing bacteria with strong alkali resistance were dominant”;
“The isolates from fast-growing rhizobium strains presented strong acid resistance, whereas those from slow-growing rhizobium strains presented strong alkali resistance. “are revised to“The isolates from slow-growing rhizobium strains presented strong acid resistance, whereas those from fast-growing rhizobium strains presented strong alkali resistance. ”
Comment 14: Finally, the authors should discuss the significance of this work. How could the results generated be applicable to agricultural and environmental developments? Furthermore, the authors should discuss any possible future work. Since RM16 stands out with good salt resistance and acid-base adaptability, is there any future work about it? As shown in the Discussion section, there is probably a relationship between fast/slow-growing status of the strains and their acid-base adaptability, could this be further investigated by genomic sequencing and/or bio-functional assays?
Response 14: Thanks for the professional questions.
In the next step of this study, the following research steps will be carried out using the isolated strains. The obtained strains will be inoculated to screen for strains that can efficiently symbiose with the host under adverse conditions (acid or salt) and study their promoting mechanisms. Then, the adaptation mechanisms of strains with strong tolerance (such as RM16) to adverse conditions will be studied, the key metabolic pathways will be analysed, and the key genes will be explored, providing strains and a foundation for enhancing the stress resistance of the rhizobia-host symbiosis and offering a gene source for the stress resistance modification of other rhizobia.
We added this passage in Section 4.2.
Comment 15: The authors should examine the manuscript and replace the non-scientific languages with professional nomenclatures.
Response 15: Thanks for the professional questions. the non-scientific languages are replaced to professional nomenclatures.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors have addressed most of the comments. The manuscript could be accepted after grammar checking.
Author Response
Reply to reviewers' comments
Manuscript ID: microbiolres-3529706
Type of manuscript: Article
Title: Identification and evaluation of the salt and acid‒alkaline
resistance of rhizobium species of Desmodium
Authors: Yunchi Zhu, An Hu, Xinyong Li, Lijuan Luo, Rongshu Dong *
Dear editor,
First of all, we would like to express our sincere thanks for your decision and your valuable comments and suggestions. Each of these comments is not only of great value to our revision in this manuscript but also helpful for us to further our understanding in the studying field. We have revised our manuscript point-by-point after carefully considering your comments. Here, we list below our responses to the comments/suggestions.
Please contact me if there are any other questions. Thank you very much for your help.
We are looking forward to hearing from you soon.
Sincerely yours,
Rongshu Dong, Ph. D
----------------------------------------------------------------------------------------------------------------------
Revised portions are marked in red in the manuscript and the responds to the reviewers’ comments point by point are as follows:
Reviewer #1:
The comments are as follows:
Comment 1: The authors have addressed most of the comments. The manuscript could be accepted after grammar checking.
Response 1: Thanks for the professional questions. The grammars are checked in our revised manuscript.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe reviewer thanks the authors for addressing these comments one-by-one.
Most of the replies satisfy the purposes of the comments, and the corresponding revisions to the original manuscript improve the readability and rigor of this manuscript.
However, the reviewer found several major issues that need further attention from the authors.
- The authors did not fully understand the purpose of original comment #7 about adding “informative figure captions” to Figure 2 (original version), or Figure 3 (revised version).
Figure 3 shows representative images of the results shown in Table 1.
- These images are assumed to be from one certain strain of Desmodium rhizobia, but the readers don’t know which one, so please add in the caption “which strain this is” -- is it RM16, DY8, or BY1, or anything else?
- While table 1 shows 5 salt concentrations, there are only 4 images shown in Figure 3. What are the 4 salt concentrations used here? Which concentration is missing? Please label clearly so that the readers understand.
- It seems that two methodologies were used to determine the growth status of the strains: one is determined by the authors “eyeballing” the growth of a strain in a culture dish, of which the results are shown in table 1 and Figure 3; the other is by OD600 values, which are presumably measured by a spectrophotometer. These details are neither included in the method section nor the caption of Figure 3, and could potentially be confusing to the readers.
Therefore, please add these details where appropriate.
- Related to original comment #13,
- For Figure 4 and 5, why are there only 49 strains in the plots, while there are 52 strains shown in Table 1? Why are ZF3, LY4 and LY5 not included in Figures 4 and 5? The authors should clarify.
- The authors should list clearly which strains are slow-growing, and which are fast-growing, among the 49 (or 52, see 1) above) strains tested for salt and pH tolerance. This is important and will be very helpful for the readers to understand the conclusions.
- Figures 4 and 5 are too “crowded” to clearly deliver any conclusions that the authors would like to make.
With 49 strains crowded into one plot, most of the symbols and lines are overlapped, and it is very difficult for the readers to differentiate among strains. This is less of an issue for Figure 4, since results shown in Table 1 provides a benchmark for it to some extent. However, this issue is severe for Figure 5. Due to this presentation issue, the readers cannot make sense of any conclusions made about the relationships between growth rate vs. acid/base tolerance, as mentioned in original comment #13.
The reviewer suggests that the authors should add another table, similar as Table 1, to demonstrate the effects of different pH values on the growth of Desmodium rhizobia. It is not necessary to include all the timepoints. For example, it could only include data at 120h (5-day). The growth status could be demonstrated as the actual OD600 values (as shown in Figure 5), or it could be converted to “+++/++/+/-” based on the control samples (pH 7.0 data).
This way the data could be presented in a much clearer manner and the conclusions would be more convincing.
- Minor glitch: there is an “ALT +V” label mistakenly snapped into the Figure 4.1 (0 mol/L NaCl). Please fix, and double check all other figures for similar issues.
Author Response
Reply to reviewers' comments
Manuscript ID: microbiolres-3529706
Type of manuscript: Article
Title: Identification and evaluation of the salt and acid‒alkaline
resistance of rhizobium species of Desmodium
Authors: Yunchi Zhu, An Hu, Xinyong Li, Lijuan Luo, Rongshu Dong *
Dear editor,
First of all, we would like to express our sincere thanks for your decision and your valuable comments and suggestions. Each of these comments is not only of great value to our revision in this manuscript but also helpful for us to further our understanding in the studying field. We have revised our manuscript point-by-point after carefully considering your comments. Here, we list below our responses to the comments/suggestions.
Please contact me if there are any other questions. Thank you very much for your help.
We are looking forward to hearing from you soon.
Sincerely yours,
Rongshu Dong, Ph. D
----------------------------------------------------------------------------------------------------------------------
Revised portions are marked in red in the manuscript and the responds to the reviewers’ comments point by point are as follows:
Reviewer #2: Major concerns
The comments are as follows:
Comment 1: 1.The authors did not fully understand the purpose of original comment #7 about adding “informative figure captions” to Figure 2 (original version), or Figure 3 (revised version).
Response 1:Thanks for the professional questions.“informative figure captions”are added to Figure 3.
Note: Figure 3 is an example of strain BY3, ‘++++’, ‘++’, ‘+’ and ‘-’ indicate the growth of strain BY3 in different concentrations of medium，(+++) indicates strong salt tolerance, (++) indicates some salt tolerance, (+) indicates weak salt tolerance, and (-) indicates no salt tolerance.
Comment 2: These images are assumed to be from one certain strain of Desmodium rhizobia, but the readers don’t know which one, so please add in the caption “which strain this is” -- is it RM16, DY8, or BY1, or anything else?.
Response 2:Thanks for the professional questions.It is the strain BY3, we add this content in Figure 3 .
Comment 3: While table 1 shows 5 salt concentrations, there are only 4 images shown in Figure 3. What are the 4 salt concentrations used here? Which concentration is missing? Please label clearly so that the readers understand
.
Response 3:Thanks for the professional questions. the 4 salt concentrations used in Figure 3 are 0.1mol/L, 0.3mol/L, 0.35mol/L and 0.4mol/L.we add this content in Figure 3 .
Comment 4: It seems that two methodologies were used to determine the growth status of the strains: one is determined by the authors “eyeballing” the growth of a strain in a culture dish, of which the results are shown in table 1 and Figure 3; the other is by OD600 values, which are presumably measured by a spectrophotometer. These details are neither included in the method section nor the caption of Figure 3, and could potentially be confusing to the readers.
Response 4:Thanks for the professional questions.
“The 52 strains to be tested were picked out from YMA slant medium, activated in YMA solid medium, and cultured in an incubator at 28°C for 5 d. The colonies were picked out with sterilised toothpick segments (1 cm) and inoculated into liquid medium with different NaCl concentrations, respectively, and cultured at 180 r.min-1 on a shaker at 28°C, timed, and cultured until 12 h. A portion of bacterial liquid was taken by pipette gun, and the absorbance value of the bacterial liquid OD600 nm was measured spectrophotometrically . The absorbance value of OD600 nm of the bacterial liquid was measured by spectrophotometer, and 3 replicates were measured for each strain, and the culture was continued after the bacterial liquid was taken, and then it was measured once every 12 h until 168 h, with a total of 14 measurements”.
We add these content in section 2.6.
Comment 5: For Figure 4 and 5, why are there only 49 strains in the plots, while there are 52 strains shown in Table 1? Why are ZF3, LY4 and LY5 not included in Figures 4 and 5? The authors should clarify.
Response 5: Thanks for the professional questions.A total of 52 strains were used for the determination of salt and acid resistance, but strains ZF3, LY4 and LY5 were not shown in the graph because they were hidden when the graph was made, and the relevant data have been added in Figures 4 and 5.
Comment 6: The authors should list clearly which strains are slow-growing, and which are fast-growing, among the 49 (or 52, see 1) above) strains tested for salt and pH tolerance. This is important and will be very helpful for the readers to understand the conclusions.
Response 6: Thanks for the professional questions.We add strain type (fast-growing, slow-growing) to Table 1, and included analyses of the correlation between strains fast-growing rhizobia and slow-growing rhizobia and salt tolerance.
Comment 7: Figures 4 and 5 are too “crowded” to clearly deliver any conclusions that the authors would like to make.
Response 7: Thanks for the professional questions. We revise the Figures 4 and 5 in the manuscript.
Comment 8: With 49 strains crowded into one plot, most of the symbols and lines are overlapped, and it is very difficult for the readers to differentiate among strains. This is less of an issue for Figure 4, since results shown in Table 1 provides a benchmark for it to some extent. However, this issue is severe for Figure 5. Due to this presentation issue, the readers cannot make sense of any conclusions made about the relationships between growth rate vs. acid/base tolerance, as mentioned in original comment #13.
The reviewer suggests that the authors should add another table, similar as Table 1, to demonstrate the effects of different pH values on the growth of Desmodium rhizobia. It is not necessary to include all the timepoints. For example, it could only include data at 120h (5-day). The growth status could be demonstrated as the actual OD600 values (as shown in Figure 5), or it could be converted to “+++/++/+/-” based on the control samples (pH 7.0 data).
Response 8: Thanks for the professional questions.In order to give the reader a clearer understanding of the effect of different treatments on the growth of the strains, the OD600 values of the different strains under different salt (acid) treatments for different times are included in the Table 2 and Table 3 .
Comment 9: 1.Minor glitch: there is an “ALT +V” label mistakenly snapped into the Figure 4.1 (0 mol/L NaCl). Please fix, and double check all other figures for similar issues.
Response 9: Thanks for the professional questions.The images have been checked, optimised and replaced in accordance with the comments of the reviewers.
