The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i>
Arginine-rich peptides can have broad-spectrum anti-bacterial and anti-fungal activities. Polyhomoarginine consists of highly cationic residues which can act on the negatively charged microbial cell membranes. <i>Acanthamoeba</i> is a free-living protozoan known to cause a rare corneal i...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-11-01
|
| Series: | Biology |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2079-7737/11/12/1726 |
| _version_ | 1797461385844621312 |
|---|---|
| author | Hari Kumar Peguda Rajamani Lakshminarayanan Nicole A. Carnt Zi Gu Mark D. P. Willcox |
| author_facet | Hari Kumar Peguda Rajamani Lakshminarayanan Nicole A. Carnt Zi Gu Mark D. P. Willcox |
| author_sort | Hari Kumar Peguda |
| collection | DOAJ |
| description | Arginine-rich peptides can have broad-spectrum anti-bacterial and anti-fungal activities. Polyhomoarginine consists of highly cationic residues which can act on the negatively charged microbial cell membranes. <i>Acanthamoeba</i> is a free-living protozoan known to cause a rare corneal infection which is difficult to diagnose and treat. This study evaluated the activity of the polyhomoarginines against <i>Acanthamoeba castellanii</i>. <i>Acanthamoeba</i> amoebicidal, amoebistatic, encystation and excystment assays were performed using protocols described in the literature. The activity of polyhomoarginines (PHAs) of different lengths (10 to 400 residues) was measured against the trophozoites and cysts of <i>Acanthamoeba castellanii</i> ATCC30868 in concentrations ranging from 0.93 μM to 15 μM. Data were represented as mean ± SE and analysed using one-way ANOVA. Overall, PHAs demonstrated good anti-acanthamoeba activity against both trophozoites and cysts. PHA 30 reduced the number of viable trophozoites by 99%, inhibited the formation of cysts by 96% and the emergence of trophozoites from cysts by 67% at 3.75 μM. PHA 10 was similarly active, but at a slightly higher concentration of 15 μM, reducing the numbers of viable trophozoites by 98%, inhibiting cyst formation by 84% and preventing the emergence of trophozoites from cysts by 99%. At their greatest anti-amoeba concentrations, PHA 10 gave only 8% haemolysis at 15 μM while PHA 30 gave <40 % haemolysis at 3.75 μM. Polyhomoarginine 10 showed excellent anti-amoebic activity against both forms of <i>Acanthamoeba castellanii</i> and was non-toxic at its most active concentrations. This implies that polyhomoarginines can be developed into a potential therapeutic agent for <i>Acanthamoeba</i> keratitis. However, there is a need to carry out further pre-clinical and then in vivo experiments in the AK animal model. |
| first_indexed | 2024-03-09T17:19:39Z |
| format | Article |
| id | doaj.art-e5b8068a3f814d61a08e9e7fb48d9df3 |
| institution | Directory Open Access Journal |
| issn | 2079-7737 |
| language | English |
| last_indexed | 2024-03-09T17:19:39Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Biology |
| spelling | doaj.art-e5b8068a3f814d61a08e9e7fb48d9df32023-11-24T13:22:22ZengMDPI AGBiology2079-77372022-11-011112172610.3390/biology11121726The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i>Hari Kumar Peguda0Rajamani Lakshminarayanan1Nicole A. Carnt2Zi Gu3Mark D. P. Willcox4School of Optometry and Vision Science, University of New South Wales, Sydney 2052, AustraliaOcular Infections and Anti-Microbials Research Group, Singapore Eye Research Institute, Singapore 169856, SingaporeSchool of Optometry and Vision Science, University of New South Wales, Sydney 2052, AustraliaSchool of Chemical Engineering, University of New South Wales, Sydney 2052, AustraliaSchool of Optometry and Vision Science, University of New South Wales, Sydney 2052, AustraliaArginine-rich peptides can have broad-spectrum anti-bacterial and anti-fungal activities. Polyhomoarginine consists of highly cationic residues which can act on the negatively charged microbial cell membranes. <i>Acanthamoeba</i> is a free-living protozoan known to cause a rare corneal infection which is difficult to diagnose and treat. This study evaluated the activity of the polyhomoarginines against <i>Acanthamoeba castellanii</i>. <i>Acanthamoeba</i> amoebicidal, amoebistatic, encystation and excystment assays were performed using protocols described in the literature. The activity of polyhomoarginines (PHAs) of different lengths (10 to 400 residues) was measured against the trophozoites and cysts of <i>Acanthamoeba castellanii</i> ATCC30868 in concentrations ranging from 0.93 μM to 15 μM. Data were represented as mean ± SE and analysed using one-way ANOVA. Overall, PHAs demonstrated good anti-acanthamoeba activity against both trophozoites and cysts. PHA 30 reduced the number of viable trophozoites by 99%, inhibited the formation of cysts by 96% and the emergence of trophozoites from cysts by 67% at 3.75 μM. PHA 10 was similarly active, but at a slightly higher concentration of 15 μM, reducing the numbers of viable trophozoites by 98%, inhibiting cyst formation by 84% and preventing the emergence of trophozoites from cysts by 99%. At their greatest anti-amoeba concentrations, PHA 10 gave only 8% haemolysis at 15 μM while PHA 30 gave <40 % haemolysis at 3.75 μM. Polyhomoarginine 10 showed excellent anti-amoebic activity against both forms of <i>Acanthamoeba castellanii</i> and was non-toxic at its most active concentrations. This implies that polyhomoarginines can be developed into a potential therapeutic agent for <i>Acanthamoeba</i> keratitis. However, there is a need to carry out further pre-clinical and then in vivo experiments in the AK animal model.https://www.mdpi.com/2079-7737/11/12/1726<i>Acanthamoeba</i>free-living amoebaantimicrobial peptidesarginine peptidespolyhomoarginine |
| spellingShingle | Hari Kumar Peguda Rajamani Lakshminarayanan Nicole A. Carnt Zi Gu Mark D. P. Willcox The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i> Biology <i>Acanthamoeba</i> free-living amoeba antimicrobial peptides arginine peptides polyhomoarginine |
| title | The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i> |
| title_full | The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i> |
| title_fullStr | The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i> |
| title_full_unstemmed | The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i> |
| title_short | The Activity of Polyhomoarginine against <i>Acanthamoeba castellanii</i> |
| title_sort | activity of polyhomoarginine against i acanthamoeba castellanii i |
| topic | <i>Acanthamoeba</i> free-living amoeba antimicrobial peptides arginine peptides polyhomoarginine |
| url | https://www.mdpi.com/2079-7737/11/12/1726 |
| work_keys_str_mv | AT harikumarpeguda theactivityofpolyhomoarginineagainstiacanthamoebacastellaniii AT rajamanilakshminarayanan theactivityofpolyhomoarginineagainstiacanthamoebacastellaniii AT nicoleacarnt theactivityofpolyhomoarginineagainstiacanthamoebacastellaniii AT zigu theactivityofpolyhomoarginineagainstiacanthamoebacastellaniii AT markdpwillcox theactivityofpolyhomoarginineagainstiacanthamoebacastellaniii AT harikumarpeguda activityofpolyhomoarginineagainstiacanthamoebacastellaniii AT rajamanilakshminarayanan activityofpolyhomoarginineagainstiacanthamoebacastellaniii AT nicoleacarnt activityofpolyhomoarginineagainstiacanthamoebacastellaniii AT zigu activityofpolyhomoarginineagainstiacanthamoebacastellaniii AT markdpwillcox activityofpolyhomoarginineagainstiacanthamoebacastellaniii |