Various enzymes are widely used in industrial fields such as detergent, food, and feed production; leather and textile processing; pharmaceutical production; diagnostics; and waste management. The largest world market for industrial enzymes is the detergent industry. Detergent enzymes account for approximately 30–40% of the total worldwide enzyme production except for diagnostic and therapeutic enzymes. Alkaline enzymes, such as protease, α-amylase, cellulase (endo-1,4-β-glucanase), mannanase and lipase, are incorporated into heavy-duty laundry and dishwashing detergents (Ito et al. 1998; Horikoshi 1999). Most of the alkaline enzymes for detergents were first found by Horikoshi between the 1960s and 1980s. Owing to his discovery of the world of alkaliphiles, detergents containing such alkaline enzymes have been expanded worldwide and established their importance and necessity in the detergent industry.
In 1959, the first detergent that contained a bacterial protease appeared on the...
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Aehle W (1997) Development of new amylases. In: van Ee JH, Misset O, Baas EJ (eds) Enzymes in detergency. Marcel Dekker, New York, pp 213–229
Ara K, Igarashi K, Saeki K, Kawai S, Ito S (1992) Purification and some properties of an alkaline pullulanase from alkalophilic Bacillus sp. KSM-1876. Biosci Biotechnol Biochem 56:62–65
Ara K, Saeki K, Ito S (1993) Purification and characterization of an alkaline isoamylase from an alkalophilic strain of Bacillus. J Gen Microbiol 139:781–786
Ara K, Saeki K, Igarashi K, Takaiwa M, Uemura T, Hagihara H, Kawai S, Ito S (1995) Purification and characterization of an alkaline amylopullulanase with both α-1, 4 and α-1, 6 hydrolytic activity from alkalophilic Bacillus sp. KSM-1378. Biochim Biophys Acta 1243:315–324
Betzel C, Klupsch S, Papendorf G, Hastrup S, Branner S, Wilson KS (1992) Crystal structure of the alkaline proteinase SavinaseTM from Bacillus lentus at 1.4 Å resolution. J Mol Biol 223:427–445
Bott R, Ultsch M, Kossiakoff A, Graycar T, Katz B, Power S (1988) The three-dimensional structure of Bacillus amyloliquefaciens subtilisin at 1.8 Å and analysis of the structural consequence of peroxide inactivation. J Biol Chem 263:7895–7906
Boyer EW, Ingle MB (1972) Extracellular alkaline amylase from a Bacillus species. J Bacteriol 110:992–1000
Bryan PN (2000) Protein engineering of subtilisin. Biochim Biophys Acta 1543:203–222
Buisson GE, Duée R, Haser R, Pyan F (1987) Three dimensional structure of porcine α-amylase at 2.9 Å resolution. Role of calcium in structure and activity. EMBO J 6:3909–3916
Davies GJ, Dauter M, Brzozowski M, Bjornvad ME, Andersen KV, Schülein M (1998) Structure of the Bacillus agaradherens family 5 endoglucanase at 1.6 Å and its cellobiose complex at 2.0 Å resolution. Biochemistry 37:1926–1932
Davies GJ, Brzozowski AM, Dauter Z, Rasmussen MD, Borchert TV, Wilson KS (2005) Structure of Bacillus halmapalus family 13 α-amylase, BHA, in complex with a acarbose-derived nonasaccharide at 2.1 Å resolution. Acta Crystallogr D Biol Crystallogr 61:190–193
Declerck N, Joyet P, Trosset JY, Garnier J, Gaillardin C (1995) Hyperthermostable mutants of Bacillus licheniformis α-amylase: multiple amino acid replacements and molecular modeling. Protein Eng 8:1029–1037
Declerck N, Machius M, Chambert R, Wiegand G, Huber R, Gaillardin C (1997) Hyperthermostable mutants of Bacillus licheniformis α-amylase; thermodynamic studies and structural interpretation. Protein Eng 10:541–549
Egmond MR (1997) Application of proteases in detergents. In: van Ee JH, Misset O, Baas EJ (eds) Enzymes in detergency. Marcel Dekker, New York, pp 61–74
Estell DA, Graycar TP, Wells JA (1985) Engineering an enzyme by site-directed mutagenesis to be resistant to chemical oxidation. J Biol Chem 260:6518–6521
Fukumori F, Kudo T, Narahashi Y, Horikoshi K (1985) Purification and properties of a cellulose from alkalophilic Bacillus sp. no. 1139. J Gen Microbiol 131:3339–3345
Fukumori F, Sashihara N, Kudo T, Horikoshi K (1986) Nucleotide sequences of two cellulase genes from alkalophilic Bacillus sp. strain N-4 and their strong homology. J Bacteriol 168:479–485
Fukumori F, Kudo T, Sashihara N, Nagata Y, Ito K, Horikoshi K (1989) The third gene of alkalophilic Bacillus sp. strain N-4: evolutionary relationship within the cel gene family. Gene 76:289–298
Guntelberg AV, Ottesen M (1954) Purification of the proteolytic activity from Bacillus subtilis. C R Trav Lab Carlsberg 29:36–48
Hagihara H, Hayashi Y, Endo K, Igarashi K, Ozawa T, Kawai S, Ozaki K, Ito S (2001a) Deduced amino-acid sequence of a calcium-free α-amylase from a strain of Bacillus. Implications from molecular modeling of high oxidation stability and chelator resistance of the enzyme. Eur J Biochem 268:3974–3982
Hagihara H, Igarashi K, Hayashi Y, Endo K, Ikawa-Kitamura K, Ozaki K, Kawai S, Ito S (2001b) Novel α-amylase that is highly resistant to chelating reagents and chemical oxidants from the alkaliphilic Bacillus isolate KSM-K38. Appl Environ Microbiol 6:71744–71750
Hagihara H, Igarashi K, Hayashi H, Kitayama K, Endo K, Ozawa T, Ozaki K, Kawai S, Ito S (2002) Improvement of thermostability of a calcium-free α-amylase from an alkaliphilic Bacillus sp. by protein engineering. J Appl Glycosci 49:281–289
Hagihara H, Hatada Y, Ozawa T, Igarashi K, Araki H, Ozaki K, Kobayashi T, Kawai S, Ito S (2003) Oxidative stabilization of an alkaliphilic Bacillus α-amylase by replacing a single specific methionine residue by site-directed mutagenesis. J Appl Glycosci 50:367–372
Hakamada Y, Kobayashi T, Hitomi J, Kawai S, Ito S (1994) Molecular cloning and nucleotide sequence of the gene for an alkaline protease from the alkalophilic Bacillus sp. KSM-K16. J Ferment Bioeng 78:105–108
Hakamada Y, Koike K, Yoshimatsu T, Mori H, Kobayashi T, Ito S (1997) Thermostable alkaline cellulase from an alkaliphilic isolate, Bacillus sp. KSM-S237. Extremophiles 1:151–156
Hakamada Y, Hatada Y, Koike K, Yoshimatsu T, Kawai K, Kobayashi T, Ito S (2000) Deduced amino acid sequence and possible catalytic residues of a thermostable, alkaline cellulase from an alkaliphilic Bacillus strain. Biosci Biotechnol Biochem 64:2281–2289
Hakamada Y, Hatada Y, Ozawa T, Ozaki K, Kobayashi T, Ito S (2001) Identification of thermostabilizing residues in a Bacillus alkaline cellulase by construction of chimeras from mesophilic and thermostable enzymes and site-directed mutagenesis. FEMS Microbiol Lett 195:67–72
Hatada Y, Igarashi K, Ozaki K, Ara K, Hitomi J, Kobayashi T, Kawai S, Watabe T, Ito S (1996) Amino acid sequence and molecular structure of an alkaline amylopullulanase from Bacillus that hydrolyzes α-1, 4 and α-1, 6 linkages in polysaccharides at different active sites. J Biol Chem 271:24075–24083
Hatada Y, Saito Y, Hagihara H, Ozaki K, Ito S (2001) Nucleotide and deduced amino acid sequences of an alkaline pullulanase from the alkaliphilic bacterium Bacillus sp. KSM-1876. Biochim Biophys Acta 1545:367–371
Hayashi T, Akiba T, Horikoshi K (1988) Production and purification of new maltohexaose-forming amylases alkalophilic Bacillus sp. H-167. Agric Biol Chem 52:443–448
Hirasawa K, Uchimura K, Kashiwa M, Grant WD, Ito S, Kobayashi T, Horikoshi K (2006) Salt-activated endoglucanase of a strain of alkaliphilic Bacillus agaradhaerens. Antonie Leeuwenhoek 89:211–219
Horikoshi K (1971a) Production of alkaline amylases by alkalophilic microorganisms. II. Alkaline amylase produced by Bacillus no. A-40-2. Agric Biol Chem 35:1783–1791
Horikoshi K (1971b) Production of alkaline enzymes by alkalophilic microorganisms. Part I. Alkaline protease produced by Bacillus no. 221. Agric Biol Chem 36:1407–1414
Horikoshi K (1999) Alkaliphiles: some applications of their products for biotechnology. Microbiol Mol Biol Rev 63:735–750
Horikoshi K, Nakao M, Kurono Y, Sashihara N (1984) Cellulases of an alkalophilic Bacillus strain isolated from soil. Can J Microbiol 30:774–779
Igarashi K, Ara K, Saeki K, Ozaki K, Kawai S, Ito S (1992) Nucleotide sequence of the gene that encodes a neopullulanase from an alkalophilic Bacillus. Biosci Biotechnol Biochem 56:514–516
Igarashi K, Hatada Y, Hagihara H, Saeki K, Takaiwa M, Uemura T, Ara K, Ozaki K, Kawai S, Kobayashi T, Ito S (1998a) Enzymatic properties of a novel liquefying α-amylase from an alkaliphilic Bacillus isolate and entire nucleotide and amino acid sequences. Appl Environ Microbiol 64:3282–3289
Igarashi K, Hatada Y, Ikawa K, Araki H, Ozawa T, Kobayashi T, Ozaki K, Ito S (1998b) Improved thermostability of a Bacillus α-amylase by deletion of an arginine-glycine residue is caused by enhanced calcium binding. Biochem Biophys Res Commun 248:372–377
Igarashi K, Ozawa T, Ikawa-Kitayama K, Hayashi Y, Araki H, Endo K, Hagihara H, Ozaki K, Kawai S, Ito S (1999) Thermostabilization by proline substitution in an alkaline, liquefying α-amylase from Bacillus sp. strain KSM-1378. Biosci Biotechnol Biochem 63:1535–1540
Ikawa K, Araki H, Tsujino Y, Hayashi Y, Igarashi K, Hatada Y, Hagihara H, Ozawa T, Ozaki K, Kobayashi T, Ito S (1998) Hyperexpression of the gene for a Bacillus α-amylase in Bacillus subtilis cells; enzymatic properties and crystallization of the recombinant enzyme. Biosci Biotechnol Biochem 62:1720–1725
Ito S, Shikata S, Ozaki K, Kawai S, Okamoto K, Inoue S, Takei A, Ohta Y, Satoh T (1989) Alkaline cellulase for laundry detergents: production by Bacillus sp. KSM-635 and enzymatic properties. Agric Biol Chem 53:1275–1281
Ito S, Kobayashi T, Ara K, Ozaki K, Kawai S, Hatada Y (1998) Alkaline detergent enzymes from alkaliphiles: enzymatic properties, genetics, and structures. Extremophiles 2:185–190
Ito S, Hatada Y, Ozawa T, Hagihara H, Araki H, Tsujino Y, Kitayama K, Igarashi K, Kageyama Y, Kobayashi T, Ozaki K (2002) Protein-engineered Bacillus α-amylases that have acquired both enhanced thermostability and chelator resistance. J Appl Glycosci 49:257–264
Joyet P, Declerck N, Gaillardin C (1992) Hyperthermostable variants of highly thermostable alpha-amylase. Biotechnology 10:1579–1583
Kageyama Y, Takaki Y, Shimamura S, Nishi S, Nogi Y, Uchimura K, Kobayashi T, Hitomi J, Ozaki K, Kawai S, Ito S, Horikoshi K (2007) Intragenomic diversity of the V1 regions of 16S rRNA genes in high-alkaline protease-producing Bacillus calusii spp. Extremophiles 11:597–603
Kanai R, Haga K, Akiba T, Yamane K, Harata K (2004) Biochemical and crystallographic analyses of maltohexaose-producing amylase from alkalophilic Bacillus sp. 707. Biochemistry 43:14047–14056
Kawaminami S, Ozaki K, Sumitomo N, Hayashi Y, Ito S, Shimada I, Arata Y (1994) A stable isotope-aided NMR study of the active site of an endoglucanase from a strain of Bacillus. J Biol Chem 269:28752–28756
Kawaminami S, Takahashi H, Ito S, Arata Y, Shimada I (1999) A multinuclear NMR study of the active site of an endoglucanase from a strain of Bacillus: use of Trp residues as structural probes. J Biol Chem 274:19823–19828
Kim DW, Matsuzawa H (2000) Requirement for the COOH-terminal pro-sequence in the translocation of aqualysin I across the cytoplasmic membrane in Escherichia coli. Biochem Biophys Res Commun 277:216–220
Kim TU, Goo BG, Jing JY, Bun SM, Shin YC (1995) Purification and characterization of maltotetraose-forming alkaline α-amylase from an alkalophilic Bacillus strain, GM8901. Appl Environ Microbiol 61:3105–3112
Kim DW, Lin SJ, Morita S, Terada I, Matsuzawa H (1997) A carboxy-terminal pro-sequence of aqualysin I prevents proper folding of the protease domain on its secretion by Saccharomyces cerevisiae. Biochem Biophys Res Commun 231:535–539
Kobayashi T, Hakamada Y, Adachi S, Hitomi J, Yoshimatsu T, Koike K, Kawai S, Ito S (1995) Purification and properties of an alkaline protease from alkaliphilic Bacillus sp. KSM-K16. Appl Microbiol Biotechnol 43:473–481
Kobayashi T, Hakamada Y, Hitomi J, Koike K, Ito S (1996) Purification of alkaline proteases from a Bacillus strain and their possible interrelationship. Appl Microbiol Biotechnol 45:63–71
Kobayashi T, Kageyama Y, Sumitomo N, Saeki K, Shirai T, Ito S (2005) Contribution of a salt bridge triad to the thermostability of a highly alkaline protease from an alkaliphilic Bacillus strain. World J Microbiol Biotechnol 21:961–967
Kottwitz B, Upadek H (1997) Application of cellulases that contribute to color revival and softening. In: van Ee JH, Misset O, Baas EJ (eds) Enzymes in detergency. Marcel Dekker, New York, pp 133–148
Kumar S, Tsai CJ, Nussinov R (2000) Factors enhancing protein thermostability. Protein Eng 13:179–191
Lyublinskaya LA, Belyaev SV, Strongin AYA, Matyash LF, Levin ED, Stepanov VM (1974) A new chromogenic substrate for subtilisin. Anal Biochem 62:371–376
MacGuffin LJ, Bryson K, Jones DT (2000) The PSIPRED protein structure prediction server. Bioinformatics 16:404–405
Machius M, Deckerck N, Huber R, Wiegand G (1998) Activation of Bacillus licheniformis α-amylase through a disorder → order transition of the substrate-binding site mediated by a calcium-sodium-calcium metal triad. Structure 6:281–292
Manning GB, Campbell LL (1961) Thermostable α-amylase of Bacillus stearotherophilus. J Biol Chem 236:2952–2957
Markland FS, Smith EL (1971) Subtilisins: primary structure, chemical and physical properties. In: Boyer RD (ed) The enzymes, 3rd edn. Academic, New York/London, pp 561–608
Maurer KL (1997) Development of new cellulases. In: van Ee JH, Misset O, Baas EJ (eds) Enzymes in detergency. Marcel Dekker, New York, pp 175–202
Misset O (1997) Development of new lipases. In: van Ee JH, Misset O, Baas EJ (eds) Enzymes in detergency. Marcel Dekker, New York, pp 107–131
Murzin AG, Brenner SE, Hubbard T, Chothia C (1995) SOCP: a structural classification of proteins database for the investigation of sequences and structures. J Mol Biol 247:536–540
Nielsen P, Fritze D, Priest FG (1995) Phenetic diversity of alkaliphilic Bacillus strains: proposal for nine new species. Microbiology 141:1745–1761
Nogi Y, Takami H, Horikoshi K (2005) Characterization of alkaliphilic Bacillus strains used in industry: proposal of five novel species. Int J Syst Evol Microbiol 55:2309–2315
Nonaka T, Fujihashi M, Kita A, Hagihara H, Ozaki K, Ito S, Miki K (2003) Crystal structure of calcium-free α-amylase from Bacillus sp. strain KSM-K38 (AmyK38) and its sodium ion binding sites. J Biol Chem 278:24818–24824
Nonaka T, Hujihashi M, Kita A, Saeki K, Ito S, Horikoshi K, Miki K (2004) The crystal structure of an oxidatively stable subtilisin-like alkaline serine protease, KP-43, with a C-terminal α-barrel domain. J Biol Chem 279:47344–47351
Okoshi H, Ozaki K, Shikata S, Oshino K, Kawai S, Ito S (1990) Purification and characterization of multiple carboxymethyl cellulases from Bacillus sp. KSM-522. Agric Biol Chem 54:83–89
Ozaki K, Shikata S, Kawai S, Ito S, Okamoto K (1990) Molecular cloning and nucleotide sequence of a gene for alkaline cellulase from Bacillus sp. KSM-635. J Gen Microbiol 136:1327–1334
Ozaki K, Hayashi Y, Sumitomo N, Kawai S, Ito S (1995) Construction, purification, and properties of a truncated alkaline endoglucanase from Bacillus sp. KSM-635. Biosci Biotechnol Biochem 59:1613–1618
Ozawa T, Hakamada Y, Hatada Y, Kobayashi T, Shirai T, Ito S (2001) Thermostabilization of replacing of specific residues with lysine in a Bacillus alkaline cellulase: building a structural model and implication of newly formed double intrahelical salt bridges. Protein Eng 14:501–504
Ozawa T, Igarashi K, Ozaki K, Kobayashi T, Suzuki A, Shirai T, Yamane T, Ito S (2006) Molecular modeling and implications of a Bacillus α-amylase that acquires enhanced thermostability and chelator resistance by deletion of an arginine-glycine residue. J Appl Glycosci 53:193–197
Ozawa T, Endo K, Igarashi K, Kitayama K, Hayashi Y, Hagihara H, Kawai S, Ito S, Ozaki K (2007) Improvement of the thermal stability of a calcium-free, alkaline α-amylase by site-directed mutagenesis. J Appl Glycosci 54:77–83
Saeki K, Okuda M, Hatada Y, Kobayashi T, Ito S, Takami H, Horikoshi K (2000) Novel oxidatively stable subtilisin-like serine proteases from alkaliphilic Bacillus spp.: enzymatic properties, sequences, and evolutionary relationships. Biochem Biophys Res Commun 279:313–319
Saeki K, Hitomi J, Okuda M, Hatada Y, Kageyama Y, Takaiwa M, Kubota H, Hagihara H, Kobayashi T, Kawai S, Ito S (2002) A novel species of alkaliphilic Bacillus that produces an oxidatively stable alkaline serine protease. Extremophiles 6:65–72
Saito N (1973) A thermostable extracellular α-amylase from Bacillus licheniformis. Arch Biochem Biophys 155:290–298
Shaw A, Bott R, Vonrhein C, Bricogne G, Power S, Day AG (2002) A novel combination of two classic catalytic schemes. J Mol Biol 320:303–309
Shikata S, Saeki K, Okoshi H, Yoshimatsu T, Ozaki K, Kawai S, Ito S (1990) Alkaline cellulases for laundry detergents: production by alkalophilic strains of Bacillus and some properties of the crude enzymes. Agric Biol Chem 54:91–96
Shirai T, Suzuki A, Yamane T, Ashida T, Kobayashi T, Hitomi J, Ito S (1997) High-resolution crystal structure of M-protease: phylogeny aided analysis of the high-alkaline adaptation mechanism. Protein Eng 10:627–634
Shirai T, Ishida H, Noda J, Yamane T, Ozaki K, Hakamada Y, Ito S (2001) Crystal structure of alkaline cellulase K: insight into the alkaline adaptation of an industrial enzyme. J Mol Biol 310:1079–1108
Shirai T, Igarashi K, Ozawa T, Hagihara H, Kobayashi T, Ozaki K, Ito S (2007) Ancestral sequence evolutionary trace and crystal structure analyses of alkaline α-amylase from Bacillus sp. KSM-1378 to clarify the alkaline adaptation process of proteins. Proteins 66:600–610
Siezen RJ, Leunissen JAM (1997) Subtilases: the superfamily of subtilisin-like serine proteases. Protein Sci 6:501–523
Stauffer CE, Etson D (1969) The effect on subtilisin activity of oxidizing a methionine residue. J Biol Chem 244:5333–5338
Sumitomo N, Ozaki K, Kawai S, Ito S (1992) Nucleotide sequence of the gene for an alkaline endoglucanase from an alkalophilic Bacillus and its expression in Escherichia coli and Bacillus subtilis. Biosci Biotechnol Biochem 56:872–877
Sumitomo N, Ozaki K, Hitomi J, Kawaminami S, Kobayashi T, Kawai S, Ito S (1995) Application of the upstream region of a Bacillus endoglucanase gene to high-level expression of foreign genes in Bacillus subtilis. Biosci Biotechnol Biochem 59:2172–2175
Suzuki Y, Ito N, Yuuki T, Yamagata H, Udaka S (1989) Amino acid residues stabilizing a Bacillus α-amylase against irreversible thermoinactivation. J Biol Chem 264:18933–18938
Teather RM, Wood PJ (1982) Use of Congo red-polysaccharide interactions in enumeration and characterization cellulolytic bacteria from the bovine rumen. Appl Environ Microbiol 43:777–780
Terada I, Kwan ST, Miyata Y, Matsuzawa H, Ohta T (1990) Unique precursor structure of an extracellular protease, aqualysin I, with NH2− and COOH−terminal pro-sequences and its processing in Escherichia coli. J Biol Chem 265:6576–6581
van der Laan HM, Teplyakov AV, Kelders H, Kalk KH, Misset O, Mulleners LJ, Dijkstra BW (1992) Crystal structure of the high-alkaline serine protease PB92 from Bacillus alkalophilus. Protein Eng 5:405–411
van Ee JH (1991) A new more (bleach) stable low temperature high alkaline detergent protease. Comun J Con Esp Deterg 22:67–82
Varrot A, Schülein M, Davies GJ (2000) Insight into ligand-induced conformational change in Cel5A from Bacillus agaradhaerens revealed by a catalytically active crystal form. J Mol Biol 297:819–828
Varrot A, Schulein M, Fruchard S, Driguez H, Davies GJ (2001) Atomic resolution structure of endoglucanase Cel5A in complex with methyl 4, 4II, 4III, 4IV-tetrathio-α-cellopentoside highlights the alternative binding modes targeted by substrate mimics. Acta Crystallogr D Biol Crystallogr 57:1739–1742
Vogt G, Woell S, Argos P (1997) Protein thermal stability, hydrogen bonds, and ion pairs. J Mol Biol 269:631–643
Wells JA, Powers DB, Bott RR, Graycar TP, Estell DA (1987) Designing substrate specificity by protein engineering of electrostatic interactions. Proc Natl Acad Sci USA 84:1219–1223
Wolff AM, Showell MS (1997) Application of lipases on detergents. In: van Ee JH, Misset O, Baas EJ (eds) Enzymes in detergency. Marcel Dekker, New York, pp 93–106
Yamane T, Kani T, Hatanaka T, Suzuki A, Ashida T, Kobayashi T, Ito S, Yamashita O (1995) Structure of a new alkaline serine protease (M-protease) from Bacillus sp. KSM-K16. Acta Crystallogr D Biol Crystallogr 51:199–206
Yoshimatsu T, Ozaki K, Shikata S, Ohta Y, Koike K, Kawai S, Ito S (1990) Purification and characterization of alkaline endo-1, 4-β-glucanases from alkalophilic Bacillus sp. KSM-635. J Gen Microbiol 136:1973–1979
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Ito, S. (2011). Alkaline Enzymes in Current Detergency. In: Horikoshi, K. (eds) Extremophiles Handbook. Springer, Tokyo. https://doi.org/10.1007/978-4-431-53898-1_12
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