000			03459nas|a2200409 i 4500
005			20260818113221.0
008			020208s2001 th uzm rtt 00| a1eng d
035			_a.b11844590
099		9	_aAIT Thesis no. BP-01-03
100	0		_aDinuriah, Imastini
245	1	0	_aExtracellular expression of fungal chitin deacetylase gene in the yeast Pichia pastoris
260			_aBangkok : _bAsian Institute of Technology, _c2001
300			_a47 leaves
490	1		_aThesis ; _vno. BP-01-03
500			_aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development
502			_aThesis (M.Sc.) - Asian Institute of Technology, 2001
520			_aThe use of chitin deacetylase enzyme (CDA) for converting chitin into chitosan catches the attention of many scientists. CDA genes from various sources of organisms have been cloned into fast growing bacteria or yeasts to increase CDA production. Following the success on cloning the CDA gene from Colletotrichum lindemuthianum UPS9 into the yeast Pichia pastoris strain GS115 (Mut) and KM71 (Muts) via plasmid shuttle vector pPIC9K done by Shrestha (2000), the CDA gene expression of his recombinant clones was investigated. Selection of the best CDA producer among the recombinant clones in the expression medium was carried out based on the CDA activity of each clone on a partially deacetylated chitin substrate (PDC, 65% DD 200 mesh). CDA activity was analyzed by using Gas-Liquid Chromatography based on the release of acetic acid during the enzyme assay. Clone Cl-6 was selected as the best CDA producer out of 63 clones tested. The effect of several factors on the production and characteristics of the CDA of the best clone was also studied. The CDA production was better in buffered minimal methanol medium than in non-buffered minimal methanol medium. Enzyme levels were inhibited rather than enhanced if chitin with different levels of deacetylation was included in the expression medium. The optimum condition for CDA assay was at 50°C and pH 5.8. It was found that the CDA of clone Cl-6 was not inhibited by acetate during the enzyme assay. The test on thermostability showed that the CDA activity remaining was more than 90% even after exposing the CDA to 50°C for one hour before enzyme assay but not for more than 3 hours
650	1		_aChitin
650	1	0	_aPichia pastoris
700	1		_aStevens, Willem Frans, _eChairperson
700	1		_aSuwalee Chandrkrachang, _eExamination committee
700	1		_aSunee Nithisinprasert, _eExamination committee
700	1		_aMacaranas, Julie, _eExamination committee
710	2		_aDUE Project Batch II, LPIU - UNSOED, Indonesia, _eScholarship donor
810	2		_aAsian Institute of Technology. _tThesis ; _vno. BP-01-03
856			_3Full-Text _uhttp://203.159.5.9/ait-thesis/detail.php?q=B07823
907			_a.b11844590 _bmnait _cu
902			_a240329
998			_b0 _c020208 _dm _ea _fu _g0
945			_lmnait
945			_lmnarc
942			_c20
942			_c40
909			_aBarcode : 30050120683098 _bCREATED : 2013-06-09 _cRECORD # : i12740020 _dLPATRON : 0 _eLCHKIN : - _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 0 _jTOT RENEW : 0
909			_aBarcode : 30050120350870 _bCREATED : 2016-10-06 _cRECORD # : i13029630 _dLPATRON : 0 _eLCHKIN : - _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 0 _jTOT RENEW : 0
999			_c42658 _d42658