Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division
Bacterial cytokinesis begins with the assembly of FtsZ into a Z ring at the center of the cell. The Z-ring constriction in Gram-negative bacteria may occur in an environment where the periplasm and the cytoplasm are isoosmotic, but in Gram-positive bacteria the constriction may have to overcome a su...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2018-01-01
|
| Series: | Frontiers in Microbiology |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/article/10.3389/fmicb.2018.00111/full |
| _version_ | 1818562394139394048 |
|---|---|
| author | Masaki Osawa Harold P. Erickson |
| author_facet | Masaki Osawa Harold P. Erickson |
| author_sort | Masaki Osawa |
| collection | DOAJ |
| description | Bacterial cytokinesis begins with the assembly of FtsZ into a Z ring at the center of the cell. The Z-ring constriction in Gram-negative bacteria may occur in an environment where the periplasm and the cytoplasm are isoosmotic, but in Gram-positive bacteria the constriction may have to overcome a substantial turgor pressure. We address three potential sources of invagination force. (1) FtsZ itself may generate force by curved protofilaments bending the attached membrane. This is sufficient to constrict liposomes in vitro. However, this force is on the order of a few pN, and would not be enough to overcome turgor. (2) Cell wall (CW) synthesis may generate force by pushing the plasma membrane from the outside. However, this would probably require some kind of Brownian ratchet to separate the CW and membrane sufficiently to allow a glycan strand to slip in. The elastic element is not obvious. (3) Excess membrane production has the potential to contribute significantly to the invagination force. If the excess membrane is produced under the CW, it would force the membrane to bleb inward. We propose here that a combination of FtsZ pulling from the inside, and excess membrane pushing membrane inward may generate a substantial constriction force at the division site. This combined force generation mechanism may be sufficient to overcome turgor pressure. This would abolish the need for a Brownian ratchet for CW growth, and would permit CW to operate by reinforcing the constrictions generated by FtsZ and excess membrane. |
| first_indexed | 2024-12-14T01:03:10Z |
| format | Article |
| id | doaj.art-5d65b27b8a88491fa6c5cb5a16fcce5f |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-14T01:03:10Z |
| publishDate | 2018-01-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-5d65b27b8a88491fa6c5cb5a16fcce5f2022-12-21T23:23:06ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2018-01-01910.3389/fmicb.2018.00111331686Turgor Pressure and Possible Constriction Mechanisms in Bacterial DivisionMasaki OsawaHarold P. EricksonBacterial cytokinesis begins with the assembly of FtsZ into a Z ring at the center of the cell. The Z-ring constriction in Gram-negative bacteria may occur in an environment where the periplasm and the cytoplasm are isoosmotic, but in Gram-positive bacteria the constriction may have to overcome a substantial turgor pressure. We address three potential sources of invagination force. (1) FtsZ itself may generate force by curved protofilaments bending the attached membrane. This is sufficient to constrict liposomes in vitro. However, this force is on the order of a few pN, and would not be enough to overcome turgor. (2) Cell wall (CW) synthesis may generate force by pushing the plasma membrane from the outside. However, this would probably require some kind of Brownian ratchet to separate the CW and membrane sufficiently to allow a glycan strand to slip in. The elastic element is not obvious. (3) Excess membrane production has the potential to contribute significantly to the invagination force. If the excess membrane is produced under the CW, it would force the membrane to bleb inward. We propose here that a combination of FtsZ pulling from the inside, and excess membrane pushing membrane inward may generate a substantial constriction force at the division site. This combined force generation mechanism may be sufficient to overcome turgor pressure. This would abolish the need for a Brownian ratchet for CW growth, and would permit CW to operate by reinforcing the constrictions generated by FtsZ and excess membrane.http://journal.frontiersin.org/article/10.3389/fmicb.2018.00111/fullftsZbacterial divisiontubulincytokinesisturgor pressure |
| spellingShingle | Masaki Osawa Harold P. Erickson Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division Frontiers in Microbiology ftsZ bacterial division tubulin cytokinesis turgor pressure |
| title | Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division |
| title_full | Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division |
| title_fullStr | Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division |
| title_full_unstemmed | Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division |
| title_short | Turgor Pressure and Possible Constriction Mechanisms in Bacterial Division |
| title_sort | turgor pressure and possible constriction mechanisms in bacterial division |
| topic | ftsZ bacterial division tubulin cytokinesis turgor pressure |
| url | http://journal.frontiersin.org/article/10.3389/fmicb.2018.00111/full |
| work_keys_str_mv | AT masakiosawa turgorpressureandpossibleconstrictionmechanismsinbacterialdivision AT haroldperickson turgorpressureandpossibleconstrictionmechanismsinbacterialdivision |