Xylanase

{{Short description|Any of a class of enzymes that degrade the polysaccharide xylan into xylose}}

{{infobox enzyme

| Name = Endo-1,4-β-xylanase

| EC_number = 3.2.1.8

| CAS_number = 9025-57-4

| GO_code = 0031176

| image =

| width =

| caption =

}}

Endo-1,4-β-xylanase ({{EnzExplorer|3.2.1.8}}, systematic name 4-β-D-xylan xylanohydrolase) is any of a class of enzymes that degrade the linear polysaccharide xylan into xylose,{{cite journal | vauthors = Beg QK, Kapoor M, Mahajan L, Hoondal GS | title = Microbial xylanases and their industrial applications: a review | journal = Applied Microbiology and Biotechnology | volume = 56 | issue = 3–4 | pages = 326–338 | date = August 2001 | pmid = 11548999 | doi = 10.1007/s002530100704 | s2cid = 21581967 }} thus breaking down hemicellulose, one of the major components of plant cell walls:

: Endohydrolysis of (1→4)-β-D-xylosidic linkages in xylans

Xylanase plays a major role in micro-organisms thriving on plant sources for the degradation of plant matter into usable nutrients. Xylanases are produced by fungi, bacteria, yeast, marine algae, protozoans, snails, crustaceans, insect, seeds, etc.;{{cite journal | vauthors = Polizeli ML, Rizzatti AC, Monti R, Terenzi HF, Jorge JA, Amorim DS | title = Xylanases from fungi: properties and industrial applications | journal = Applied Microbiology and Biotechnology | volume = 67 | issue = 5 | pages = 577–591 | date = June 2005 | pmid = 15944805 | doi = 10.1007/s00253-005-1904-7 | s2cid = 22956 }} mammals do not produce xylanases. However, the principal commercial source of xylanases is filamentous fungi.

Commercial applications for xylanase include the chlorine-free bleaching of wood pulp prior to the papermaking process, and the increased digestibility of silage (in this aspect, it is also used for fermentative composting).Gulzar, Production and partial purification of Xylanase from Trichoderma longibrachiatum. Published in international conference on biotechnology and neurosciences. CUSAT, 2004.P33{{verify source|date=December 2011}}

Apart from its use in the pulp and paper industry, xylanases are also used as food additives to poultry;{{cite journal | vauthors = Baker JT, Duarte ME, Holanda DM, Kim SW | title = Friend or Foe? Impacts of Dietary Xylans, Xylooligosaccharides, and Xylanases on Intestinal Health and Growth Performance of Monogastric Animals | journal = Animals | volume = 11 | issue = 3 | pages = 609 | date = February 2021 | pmid = 33652614 | pmc = 7996850 | doi = 10.3390/ani11030609 | doi-access = free }} in wheat flour for improving dough handling and quality of baked products [https://web.archive.org/web/20131018052215/http://www.healthbread.eu/consortium/]; for the extraction of coffee, plant oils, and starch; in the improvement of nutritional properties of agricultural silage and grain feed; and in combination with pectinase and cellulase for clarification of fruit juices and degumming of plant fiber sources such as flax, hemp, jute, and ramie. A good quantity of scientific literature is available on key features of xylanase enzymes in biotechnology ranging from their screening in microbial sources to production methods, characterization, purification and applications in commercial sector.{{cite journal | vauthors = Subramaniyan S, Prema P | title = Biotechnology of microbial xylanases: enzymology, molecular biology, and application | journal = Critical Reviews in Biotechnology | volume = 22 | issue = 1 | pages = 33–64 | year = 2002 | pmid = 11958335 | doi = 10.1080/07388550290789450 | s2cid = 13386317 }}{{cite journal | vauthors = Kulkarni N, Shendye A, Rao M | title = Molecular and biotechnological aspects of xylanases | journal = FEMS Microbiology Reviews | volume = 23 | issue = 4 | pages = 411–456 | date = July 1999 | pmid = 10422261 | doi = 10.1111/j.1574-6976.1999.tb00407.x | doi-access = free }}{{cite journal | vauthors = Ahmed S, Riaz S, Jamil A | title = Molecular cloning of fungal xylanases: an overview | journal = Applied Microbiology and Biotechnology | volume = 84 | issue = 1 | pages = 19–35 | date = August 2009 | pmid = 19568746 | doi = 10.1007/s00253-009-2079-4 | s2cid = 8548871 }}{{cite journal | vauthors = Sá-Pereira P, Paveia H, Costa-Ferreira M, Aires-Barros M | title = A new look at xylanases: an overview of purification strategies | journal = Molecular Biotechnology | volume = 24 | issue = 3 | pages = 257–281 | date = July 2003 | pmid = 12777693 | doi = 10.1385/MB:24:3:257 | s2cid = 34083448 }}{{cite journal | vauthors = Alves-Prado HF, Pavezzi FC, Leite RS, de Oliveira VM, Sette LD, Dasilva R | title = Screening and production study of microbial xylanase producers from Brazilian Cerrado | journal = Applied Biochemistry and Biotechnology | volume = 161 | issue = 1–8 | pages = 333–346 | date = May 2010 | pmid = 19898784 | doi = 10.1007/s12010-009-8823-5 | s2cid = 8378197 }}{{cite journal | vauthors = Prade RA | title = Xylanases: from biology to biotechnology | journal = Biotechnology & Genetic Engineering Reviews | volume = 13 | pages = 101–131 | year = 1996 | pmid = 8948110 | doi = 10.1016/S0140-6701(97)80292-5 }}{{cite journal | vauthors = Sunna A, Antranikian G | title = Xylanolytic enzymes from fungi and bacteria | journal = Critical Reviews in Biotechnology | volume = 17 | issue = 1 | pages = 39–67 | year = 1997 | pmid = 9118232 | doi = 10.3109/07388559709146606 }}{{cite journal | vauthors = Chávez R, Bull P, Eyzaguirre J | title = The xylanolytic enzyme system from the genus Penicillium | journal = Journal of Biotechnology | volume = 123 | issue = 4 | pages = 413–433 | date = June 2006 | pmid = 16569456 | doi = 10.1016/j.jbiotec.2005.12.036 | hdl-access = free | hdl = 10533/177866 }}{{cite journal | vauthors = Geiser E, Wierckx N, Zimmermann M, Blank LM | title = Identification of an endo-1,4-beta-xylanase of Ustilago maydis | journal = BMC Biotechnology | volume = 13 | pages = 59 | date = July 2013 | pmid = 23889751 | pmc = 3737115 | doi = 10.1186/1472-6750-13-59 | doi-access = free }} High resilience to heating is required for some applications of xylanase, which can be achieved through selection of suitable microbial enzymes or by cyclization of the termini by SpyTag/SpyCatcher reaction.{{cite journal | vauthors = Gilbert C, Howarth M, Harwood CR, Ellis T | title = Extracellular Self-Assembly of Functional and Tunable Protein Conjugates from Bacillus subtilis | journal = ACS Synthetic Biology | volume = 6 | issue = 6 | pages = 957–967 | date = June 2017 | pmid = 28230977 | doi = 10.1021/acssynbio.6b00292 | doi-access = free | hdl = 10044/1/45032 | hdl-access = free }}

Additionally, xylanase is the key ingredient in the dough conditioners s500 and us500 manufactured by {{ill|Puratos|nl}}.{{cite web|url=http://www.puratos.us/products_solutions/bakery/enzymes/default.aspx |title=- Enzymes |access-date=March 29, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060719163936/http://www.puratos.us/products_solutions/bakery/enzymes/default.aspx |archive-date=July 19, 2006 }}{{full citation needed|date=November 2012}} These enzymes are used to improve the dough's workability and absorption of water.

In the future, xylanase may be used for the production of biofuel from unusable plant material.{{cite journal | vauthors = Lee CC, Wong DW, Robertson GH | title = Cloning and characterization of the xyn11A gene from Lentinula edodes | journal = The Protein Journal | volume = 24 | issue = 1 | pages = 21–26 | date = January 2005 | pmid = 15756814 | doi = 10.1007/s10930-004-0602-0 | s2cid = 5823517 }}

• {{cite web |author=Marcia Wood |date=November 29, 2005 |title=Shiitake Mushrooms' Secret May Benefit Earth-Friendly Fuels |website=Agricultural Research Service |url=http://www.ars.usda.gov/is/pr/2005/051129.htm}}