Alkaliphiles

Abstract

Alkaliphiles grow optimally or very well at pH values above 9, often between 10 and 12, but cannot grow, or grow only slowly, at more neutral pH values. The enzymology, physiology, ecology, molecular biology and genetics of alkaliphiles, as well as industrial applications of these microorganisms have been investigated extensively and several enzymes have been put to use on an industrial scale.

Keywords: alkaline enzymes; sodium ions; pH; genetics

Figure 1.

The pH dependence of alkaliphilic microorganisms. Typical growth–pH dependence of neutrophilic and alkaliphilic bacteria are shown with squares and solid circles, respectively.

Figure 2.

Distribution of alkaliphilic microorganisms in environments of various pH.

Figure 3.

A schematic representation of cytoplasmic pH regulation.

Figure 4.

Circular structure of Bacillus halodurans C‐125 genome.

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References

Aono R and Horikoshi K (1983) Chemical composition of cell walls of alkalophilic strains of Bacillus. Journal of General Microbiology 129: 1083–1087.

Grønstad A, Jaroszewicz E, Ito M et al. (1998) Physical map of alkaliphilic Bacillus firmus OF4 and detection of a large endogenous plasmid. Extremophiles 2: 447–453.

Hirota N, Kitada M and Imae Y (1981) Flagellar motors of alkalophilic Bacillus are powered by an electrochemical potential gradient of Na+. FEBS Letters 132: 278–280.

Hoondal GS, Tieari RP, Tewari R, Dahiya N and Berg QK (2002) Microbial alkaline pectinases and their industrial applications: a review. Applied Microbiology and Biotechnology 59: 409–418.

Horikoshi K (1971a) Production of alkaline enzymes by alkalophilic microorganisms. Part I. Alkaline protease produced by Bacillus no.221. Agricultural Biological Chemistry 36: 1407–1414.

Horikoshi K (1971b) Production of alkaline enzymes by alkalophilic microorganisms. Part II. Alkaline amylase produced by Bacillus no.A‐40‐2. Agricultural Biological Chemistry 35: 1783–1791.

Horikoshi K (1991) Microorganisms in Alkaline Environments pp. 6–7. Tokyo: Kodansha‐VCH.

Horikoshi K, Nakao M, Kurono Y and Sashihara N (1984) Cellulases of alkalophilic Bacillus strain isolated from soil. Canadian Journal of Microbiology 30: 774–779.

Ito M, Guffanti AA, Zemsky J, Ivey DM and Krulwich TA (1997) Role of the nhaC‐encoded Na+/H+ antiporter of alkaliphilic Bacillus firmus OF4. Journal of Bacteriology 179: 3851–3857.

Ito M, Hicks DB, Henkin TM et al. (2004) MotPS is the stator‐force generator for motility of alkaliphilic Bacillus, and its homologue is a second functional Mot in Bacillus subtilis. Molecular Microbiology 53: 1035–1049.

Jones BE, Grant WD, Duckworth AW and Owenson GG (1998) Microbial diversity of soda lakes. Extremophiles 2: 191–200.

Kitada M, Hashimoto M, Kudo T and Horikoshi K (1994) Properties of two different Na+/H+ antiport systems in alkaliphilic Bacillus sp. strain C‐125. Journal of Bacteriology 176: 6464–6469.

Krulwich TA (1995) Alkaliphiles: ‘basic’ molecular problems of pH tolerance and bioenergetics. Molecular Microbiology 15: 403–410.

Kudo T, Hino M, Kitada M and Horikoshi K (1990) DNA sequences required for the alkalophily of Bacillus sp. strain C‐125 are located close together on its chromosomal DNA. Journal of Bacteriology 172: 7282–7283.

Saeki K, Okuda M, Hatada Y et al. (2000) Novel oxidatively stable subtilisin‐like serine protease from alkaliphilic Bacillus spp.: enzymatic properties, sequences, and evolutionary relationships. Biochemical and Biophysical Research Communications 279: 313–319.

Takami T, Nakasone K, Hirama C et al. (1999) An improved physical and genetic map of the genome of alkaliphilic Bacillus halodurans C‐125. Extremophiles 3: 21–28.

Tsujii K (2002) Donnan equilibra cell walls: a pH‐homeostatics mechanism in alkaliphiles. Colloids and Surface B: Biointerfaces 24: 247–252.

Vedder A (1934) Bacillus alcalophilus n. sp. benevens enkle ervaringen met sterk alcalische voedingsbodems. Antonie van Leeuwenhoek 1: 141–147.

Yamamoto M, Tanaka Y and Horikoshi K (1972) Alkaline amylases of alkalophilic bacteria. Agricultural Biological Chemistry 36: 1819–1823.

Further Reading

Grant WD, Mwatha WE and Jones BE (1990) Alkaliphiles: ecology, diversity and applications. FEMS Microbiology Reviews 75: 255–270.

Horikoshi K (1999) Alkaliphiles. Tokyo: Kodansha.

Horikoshi K (2006) Alkaliphiles: Genetic Properties and Applications of Enzymes. Tokyo: Kodansha.

Horikoshi K and Akiba T (1982) Alkalophilic Microorganisms: A New Microbial World. Heidelberg: Springer.

Horikoshi K and Grant WD (eds) (1991) Superbugs. Heidelberg: Springer.

Horikoshi K and Grant WD (eds) (1998) Extremophiles: Microbial Life in Extreme Environments. New York: Wiley‐Liss.

Jones BE, Grant WD, Duckworth AW and Owenson GG (1998) Microbial diversity of soda lakes. Extremophiles 2: 191–200.

Kitada M and Horikoshi K (1980) Sodium‐ion stimulated amino acid uptake in membrane vesicles of alkalophilic Bacillus no. 8–1. Journal of Biochemistry 88: 1757–1764.

Kroll RG (1990) Alkaliphiles. In: Edwards C (ed.) Microbiology of Extreme Environments, pp. 55–92. New York: McGraw‐Hill.

Krulwich TA and Guffanti AA (1989) Alkalophilic bacteria. Annual Review of Microbiology 43: 435–463.

Krulwich T, Ito M, Gilmour R and Guffanti A (1997) Mechanisms of cytoplasmic pH regulation in alkaliphilic strains of Bacillus. Extremophiles 1: 163–169.

Krulwich T, Ito M, Hicks DR, Gilmour R and Guffanti A (1998) pH Homeostasis and ATP synthesis: studies of two processes that necessitate inward proton translocation in extremely alkaliphilic Bacillus species. Extremophiles 2: 217–222.

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How to Cite close
Horikoshi, Koki(Jul 2008) Alkaliphiles. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0000337.pub2]