Process Biochemistry 39 (2004) 591–598
Cloning and expression of the transglutaminase gene from
Streptoverticillium ladakanum in Streptomyces lividans
ଝ
Yi-Sin Lin, Mei-Li Chao, Chang-Hsiesh Liu, Wen-Shen Chu
∗
Food Industry Research and Development Institute, Hsinchu, Taiwan, ROC
Received 18 November 2002; accepted 6 April 2003
Abstract
A gene, tgB1, encoding transglutaminase (TGase) in Streptoverticillium ladakanum B1 was cloned and expressed in Streptomyces lividans.
ThetgB1geneconsistedofanopenreadingframeof1230nucleotidesencodingaproteinof410aminoacidswithacalculatedmolecularweight
of 45780 Da. The deduced amino acid sequence is highly homologous to TGases from Streptoverticillium spp. but exhibits little homology
with TGases of Bacillus subtilis and mammalian origins. The putative active site, YGCVG, conserved in Streptoverticillium TGases is also
present in TgB1. No −10 and −35 regions of the putative promoter could be identified. Two A+T-rich regions, characteristics of a promoter
sequence, were found at bp 238–269 and bp 631–681. The tgB1 gene was expressed in S. lividans JT46 under the control of its endogenous
promoter. Immunoblotting of SDS-PAGE revealed that, in addition to protein bands with sizes corresponding to those of the unprocessed and
mature TgB1, several bands with sizes in between reacting with anti-TgB1 IgG were present in the culture supernatant of the recombinant
strain. This suggests that the recombinant TgB1 was not correctly processed during secretion in the transformed S. lividans JT46.
© 2003 Elsevier Ltd. All rights reserved.
Keywords: Transglutaminase; Cloning; Expression; Streptoverticillium ladakanum; Streptomyces lividans
1. Introduction
Transglutaminase (TGase; protein-glutamine:amine ␥-
glutamyltransferase, EC 2.3.2.13) catalyzes an acyl transfer
reaction between a ␥-carboxyamide group of glutamine and
ε-amino group of lysine or other primary amine, result-
ing in the formation of ␥-glutamyl-ε-lysine peptide chain
bridges [1,2]. TGases are widely distributed in nature and
have been studied extensively in animals. TGases in animal
systems are Ca
+2
-dependent and involved in a wide vari-
ety of biological functions ranging from blood clotting to
cell differentiation [3]. Among them, factor XIII (plasma
TGase) and guinea pig liver TGase are the best character-
ized. Factor XIII has been purified, cloned, and sequenced
[4,5]. The cDNA for TGase from guinea pig liver has also
been cloned and expressed in Escherichia coli [6].
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The GenBank accession number for the sequence reported in this
paper is AY241675.
∗
Corresponding author. Address: FIRDI, P.O. Box 246, Hsinchu
30099, Taiwan, ROC. Tel.: +886-3-522-3191; fax: 886-3-521-4016.
E-mail address: cws@firdi.org.tw (W.-S. Chu).
There are few studies on TGase from microbial sources.
TGase activity has been found in the genus Streptoverti-
cillium spp. [7,8], Physarum polycephalum [9], Candida
albican [10], Bacillus subtilis [11], Bordetella pertussis
[12], Streptoverticillium cinnamoneum CBS 683.68 [13],
and E. coli [14]. The enzymes from Streptoverticillium
sp. S-8112 [7,15], Streptoverticillium mobaraense [16,17],
P. polycephalum [9], Streptoverticillium ladakanum [18,19],
and Sv. cinnamoneum CBS 683.68 [13] have been purified
and characterized. Genes for TGases of Streptoverticillium
sp. S-8112 [20], Sv. cinnamoneum CBS 683.68 [13], Sv.
mobaraense DSMZ strain [21], and B. subtilis [22] were
cloned and sequenced.
The TGase from Sv. ladakanum had a Mr of about 37.5
kDa as estimated by SDS-PAGE [18]. The optimal tempera-
ture and pH of the enzyme were 40
◦
C and 5.5, respectively.
It was stable at pH 5.0–7.0 and had a rate constant (K
D
)
of 6.21×10
−5
/min for thermal inactivation at 45
◦
C [19].It
was strongly inhibited by PCMB, PMSF, Pb
+2
,Zn
+2
, and
Cu
+2
, but not affected by EDTA and Ca
+2
[18].
Recently, we have conducted screening on isolates col-
lected in Taiwan for TGase activity. A Sv. ladakanum
strain B1 with high TGase activity was found. The genus
0032-9592/$ – see front matter © 2003 Elsevier Ltd. All rights reserved.
doi:10.1016/S0032-9592(03)00134-1