Halocins are bacteriocins produced by halophilic Archaea[1][2] and a type of archaeocin.[3]

Since their discovery in 1982,[4] halocins have been demonstrated to be diverse in a similar ways as the other bacteriocins.[5][6][7] Some are large proteins, some small polypeptides (microhalocins). This diversity is surprising for a number of reasons, including the original presumptions that Archaea, particularly extremophiles, live at relatively low densities under conditions that may not require antagonistic behavior.

The genetics,[8][9][10][11][12] mechanism of production[13][14] and mechanism of action[15][16][17][18] of the halocins have been studied, but not exhaustively. The ecology of the halocins[19][20][21] has been investigated as well. One interesting observation is that the halocins are active across the major divisions of archaea,[22] thus violating the dogma that they should be most effective against the most closely related strains.

Halocins are particularly interesting because of the way the pore-forming bacteriocins have been used to probe cell membrane structure and the production and maintenance of energetic ion gradients across the membrane. The halophiles live at such extreme ion concentrations that they represent a set of unusual solutions and adaptations with regard to their energetic gradients. The ability to use native halocins to study these gradients provides a motivation for their characterization.

They may have a role in human medicine.[23][24]

They are also found in many of the type species that are used to learn about halophiles in general.[25]

Like other bacteriocins, the halocins are under investigation as antimicrobials for use in controlling spoilage during industrial processes; in this case, leather production.[26]

Because the literature about halocins is relatively circumscribed, it can be exhaustively cited. Several times they have been addressed in book chapters.[3][27][28][29]

BACTIBASE[30][31] database is an open-access database for bacteriocins including halocins (view complete list).

References edit

  1. ^ Li Y, Xiang H, Tan H (2002). "[Halocin: protein antibiotics produced by extremely halophilic archaea]". Wei Sheng Wu Xue Bao (in Chinese). 42 (4): 502–5. PMID 12557560.
  2. ^ O'Connor EM, Shand RF (2002). "Halocins and sulfolobicins: the emerging story of archaeal protein and peptide antibiotics". Journal of Industrial Microbiology & Biotechnology. 28 (1): 23–31. doi:10.1038/sj/jim/7000190. PMID 11938468. S2CID 16583426.
  3. ^ a b Shand RF, Leyva KJ (2008). "Archaeal Antimicrobials: An Undiscovered Country". Archaea: New Models for Prokaryotic Biology. Caister Academic Press. ISBN 978-1-904455-27-1.
  4. ^ Rodríguez-Valera F, Juez G, Kushner DJ (1982). "Halocins: salt-dependent bacteriocins produced by extremely halophilic rod". Canadian Journal of Microbiology. 28: 151–154. doi:10.1139/m82-019.
  5. ^ Torreblanca M, Meseguer I, Rodríguez-Valera F (1989). "Halocin H6, a bacteriocin from Haloferax gibbonsii". Journal of General Microbiology. 135 (10): 2655–2661. doi:10.1099/00221287-135-10-2655.
  6. ^ Price LB, Shand RF (2000). "Halocin S8: a 36-Amino-Acid Microhalocin from the Haloarchaeal Strain S8a". Journal of Bacteriology. 182 (17): 4951–8. doi:10.1128/JB.182.17.4951-4958.2000. PMC 111376. PMID 10940040.
  7. ^ Platas G, Meseguer I, Amils R (2002). "Purification and biological characterization of halocin H1 from Haloferax mediterranei M2a". International Microbiology. 5 (1): 15–9. doi:10.1007/s10123-002-0053-4. PMID 12102231. S2CID 45501770.
  8. ^ Mei SS, Li Y, Lu QH, Xiang H (2006). "[Cloning and analysis of genes in the halocin C8 gene cluster]". Wei Sheng Wu Xue Bao (in Chinese). 46 (2): 318–22. PMID 16736600.
  9. ^ Sun C, Li Y, Mei S, Lu Q, Zhou L, Xiang H (2005). "A single gene directs both production and immunity of halocin C8 in a haloarchaeal strain AS7092". Molecular Microbiology. 57 (2): 537–49. doi:10.1111/j.1365-2958.2005.04705.x. PMID 15978083.
  10. ^ Perez, AM (2000). Growth physiology of Haloferax mediterranei R4 and purification of halocin H4. Flagstaff, Arizona: Northern Arizona University. pp. Masters Thesis.
  11. ^ Cheung J, Danna KJ, O'Connor EM, Price LB, Shand RF (1997). "Isolation, sequence, and expression of the gene encoding halocin H4, a bacteriocin from the halophilic archaeon Haloferax mediterranei R4". Journal of Bacteriology. 179 (2): 548–51. doi:10.1128/jb.179.2.548-551.1997. PMC 178729. PMID 8990311.
  12. ^ Platas G, Meseguer I, Amils R (1996). "Optimization of the production of a bacteriocin from Haloferax mediterranei Xia3". Microbiología. 12 (1): 75–84. PMID 9019137.
  13. ^ Meseguer I, Rodríguez-Valera F (1985). "Production and purification of halocin H4". FEMS Microbiology Letters. 28 (2): 177–182. doi:10.1111/j.1574-6968.1985.tb00787.x.
  14. ^ Li Y, Xiang H, Liu J, Zhou M, Tan H (2003). "Purification and biological characterization of halocin C8, a novel peptide antibiotic from Halobacterium strain AS7092". Extremophiles. 7 (5): 401–7. doi:10.1007/s00792-003-0335-6. PMID 12811620. S2CID 32609554.
  15. ^ Platas G (1995). Caracterizacíon de la actividad antimicrobiana de la haloarquea Haloferax mediterranei Xia3. Madrid, Spain: Universidad Autónoma de Madrid. pp. Doctoral Thesis.
  16. ^ Meseguer I, Torreblanca M, Konishi T (1995). "Specific inhibition of the halobacterial Na+/H+ antiporter by halocin H6". Journal of Biological Chemistry. 270 (12): 6450–5. doi:10.1074/jbc.270.12.6450. PMID 7896778.
  17. ^ Meseguer I, Rodríguez-Valera F (1986). "Effect of halocin H4 on cells of Halobacterium halobium". Journal of General Microbiology. 132 (11): 3061–3068. doi:10.1099/00221287-132-11-3061.
  18. ^ Girones F, Minagawa A, Hatano Y, Torreblanca M, Meseguer I, Sanchez M, Konishi T (2001). "Protein-protein interaction between halocin H7 and halobacterial membrane protein". Nippon Yakugakkai Nenkai Koen Yoshishu. 121 (4): 116.
  19. ^ Kis-Papo T, Oren A (2000). "Halocins: are they involved in the competition between halobacteria in saltern ponds?". Extremophiles. 4 (1): 35–41. doi:10.1007/s007920050005. PMID 10741835. S2CID 24584604.
  20. ^ Meseguer I, Rodríguez-Valera F, Ventosa A (1986). "Antagonistic interactions among halobacteria due to halocin production". FEMS Microbiology Letters. 36 (2–3): 177–182. doi:10.1111/j.1574-6968.1986.tb01691.x.
  21. ^ Oren A (1994). "The ecology of the halophilic archaea". FEMS Microbiology Reviews. 13 (4): 415–440. doi:10.1111/j.1574-6976.1994.tb00060.x.
  22. ^ Haseltine C, Hill T, Montalvo-Rodriguez R, Kemper SK, Shand RF, Blum P (2001). "Secreted Euryarchaeal Microhalocins Kill Hyperthermophilic Crenarchaea". Journal of Bacteriology. 183 (1): 287–91. doi:10.1128/JB.183.1.287-291.2001. PMC 94877. PMID 11114928.
  23. ^ Alberola A, Meseguer I, Torreblanca M, Moya A, Sancho S, Polo B, Soria B, Such L (1998). "Halocin H7 decreases infarct size and ectopic beats after mycardial reperfusion in dogs". Journal of Physiology.
  24. ^ Lequerica JL, O'Connor JE, Such L, Alberola A, Meseguer I, Dolz M, Torreblanca M, Moya A, Colom F, Soria B (2006). "A halocin acting on Na+/H+ exchanger of haloarchaea as a new type of inhibitor in NHE of mammals". Journal of Physiology and Biochemistry. 62 (4): 253–62. doi:10.1007/BF03165754. PMID 17615951. S2CID 8822522.
  25. ^ Soppa J, Oesterhelt D (1989). "Halobacterium sp. GRB: a species to work with!?". Canadian Journal of Microbiology. 35 (1): 205–9. doi:10.1139/m89-032. PMID 2720494.
  26. ^ Birbir M, Eryilmaz S, Ogan A (2004). "Prevention of halophilic microbial damage on brine cured hides by extremely halophilic halocin producer strains". Journal of the Society of Leather Technologists and Chemists. 88 (3): 99–104.
  27. ^ Rdest U, Sturm M (1987). "Bacteriocins from halobacteria". In Burgess R (ed.). Protein Purification: Micro to Macro. New York, New York: Alan R. Liss. pp. 271–278.
  28. ^ Shand RF, Perez AM (1999). "Haloarchaeal growth physiology". In Seckback J (ed.). Enigmatic Organisms and Life in Extreme Environments. Dordrecht, The Netherlands: Kluwer Acadademic Press. pp. 413–424.
  29. ^ Shand RF, Price LB, O'Connor EM (1999). "Halocins: protein antibiotics from hypersaline environments". In Oren A (ed.). Microbiology and Biogeochemistry of Hypersaline Environments. Boca Raton, FL: CRC Press. pp. 295–306.
  30. ^ Hammami R, Zouhir A, Ben Hamida J, Fliss I (2007). "BACTIBASE: a new web-accessible database for bacteriocin characterization". BMC Microbiology. 7: 89. doi:10.1186/1471-2180-7-89. PMC 2211298. PMID 17941971.
  31. ^ Hammami R, Zouhir A, Le Lay C, Ben Hamida J, Fliss I (2010). "BACTIBASE second release: a database and tool platform for bacteriocin characterization". BMC Microbiology. 10: 22. doi:10.1186/1471-2180-10-22. PMC 2824694. PMID 20105292.