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The Hypocrea jecorina (Trichoderma reesei) hypercellulolytic mutant RUT C30 lacks a 85 kb (29 gene-encoding) region of the wild-type genome.

Seidl V, Gamauf C, Druzhinina IS, Seiboth B, Hartl L, Kubicek CP - BMC Genomics (2008)

Bottom Line: The mutation of the cre1 locus has specifically occurred in RUT C30.Some of the genes that are lacking in RUT C30 could be correlated with pronounced alterations in its phenotype, such as poor growth on alpha-linked oligo- and polyglucosides (loss of maltose permease), or disturbance of osmotic homeostasis.Our data place a general caveat on the use of H. jecorina RUT C30 for further basic research.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Getreidemarkt 9/166-5, A-1060 Wien, Austria. vseidl@mail.zserv.tuwien.ac.at

ABSTRACT

Background: The hypercellulolytic mutant Hypocrea jecorina (anamorph Trichoderma reesei) RUT C30 is the H. jecorina strain most frequently used for cellulase fermentations and has also often been employed for basic research on cellulase regulation. This strain has been reported to contain a truncated carbon catabolite repressor gene cre1 and is consequently carbon catabolite derepressed. To date this and an additional frame-shift mutation in the glycoprotein-processing beta-glucosidase II encoding gene are the only known genetic differences in strain RUT C30.

Results: In the present paper we show that H. jecorina RUT C30 lacks an 85 kb genomic fragment, and consequently misses additional 29 genes comprising transcription factors, enzymes of the primary metabolism and transport proteins. This loss is already present in the ancestor of RUT C30--NG 14--and seems to have occurred in a palindromic AT-rich repeat (PATRR) typically inducing chromosomal translocations, and is not linked to the cre1 locus. The mutation of the cre1 locus has specifically occurred in RUT C30. Some of the genes that are lacking in RUT C30 could be correlated with pronounced alterations in its phenotype, such as poor growth on alpha-linked oligo- and polyglucosides (loss of maltose permease), or disturbance of osmotic homeostasis.

Conclusion: Our data place a general caveat on the use of H. jecorina RUT C30 for further basic research.

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Related in: MedlinePlus

Growth rates of H. jecorina strain QM6a (full circles) and strain RUT C30 (full triangles) on maltose, maltotriose, dextrin and starch, using the Biolog phenotype arrays system. The grey area indicates the threshold of the water control. Data are shown are means of 3 separate experiments, which differed by less than ± 10 relative %.
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Figure 5: Growth rates of H. jecorina strain QM6a (full circles) and strain RUT C30 (full triangles) on maltose, maltotriose, dextrin and starch, using the Biolog phenotype arrays system. The grey area indicates the threshold of the water control. Data are shown are means of 3 separate experiments, which differed by less than ± 10 relative %.

Mentions: The presence of a maltose permease in the missing genomic fragment raised the question whether this would have an impact of the growth of H. jecorina RUT C30 on α-linked glucans and glucosides. As can be seen from Fig. 5, growth on dextrin, starch, maltose and maltotriose was indeed strongly impaired in RUT C30, which is consistent with the absence of a maltose permease responsible for α-glucoside uptake. This interpretation is supported by the fact that H. jecorina – in contrast to several Aspergillus spp. – does not have multiple maltose permease genes (unpublished observations) and also lacks an extracellular α-glucosidase [38]. The present findings are therefore consistent with a metabolism of α-glucosides in H. jecorina by uptake and intracellular hydrolysis, which is impaired in RUT C30.


The Hypocrea jecorina (Trichoderma reesei) hypercellulolytic mutant RUT C30 lacks a 85 kb (29 gene-encoding) region of the wild-type genome.

Seidl V, Gamauf C, Druzhinina IS, Seiboth B, Hartl L, Kubicek CP - BMC Genomics (2008)

Growth rates of H. jecorina strain QM6a (full circles) and strain RUT C30 (full triangles) on maltose, maltotriose, dextrin and starch, using the Biolog phenotype arrays system. The grey area indicates the threshold of the water control. Data are shown are means of 3 separate experiments, which differed by less than ± 10 relative %.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2483294&req=5

Figure 5: Growth rates of H. jecorina strain QM6a (full circles) and strain RUT C30 (full triangles) on maltose, maltotriose, dextrin and starch, using the Biolog phenotype arrays system. The grey area indicates the threshold of the water control. Data are shown are means of 3 separate experiments, which differed by less than ± 10 relative %.
Mentions: The presence of a maltose permease in the missing genomic fragment raised the question whether this would have an impact of the growth of H. jecorina RUT C30 on α-linked glucans and glucosides. As can be seen from Fig. 5, growth on dextrin, starch, maltose and maltotriose was indeed strongly impaired in RUT C30, which is consistent with the absence of a maltose permease responsible for α-glucoside uptake. This interpretation is supported by the fact that H. jecorina – in contrast to several Aspergillus spp. – does not have multiple maltose permease genes (unpublished observations) and also lacks an extracellular α-glucosidase [38]. The present findings are therefore consistent with a metabolism of α-glucosides in H. jecorina by uptake and intracellular hydrolysis, which is impaired in RUT C30.

Bottom Line: The mutation of the cre1 locus has specifically occurred in RUT C30.Some of the genes that are lacking in RUT C30 could be correlated with pronounced alterations in its phenotype, such as poor growth on alpha-linked oligo- and polyglucosides (loss of maltose permease), or disturbance of osmotic homeostasis.Our data place a general caveat on the use of H. jecorina RUT C30 for further basic research.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Getreidemarkt 9/166-5, A-1060 Wien, Austria. vseidl@mail.zserv.tuwien.ac.at

ABSTRACT

Background: The hypercellulolytic mutant Hypocrea jecorina (anamorph Trichoderma reesei) RUT C30 is the H. jecorina strain most frequently used for cellulase fermentations and has also often been employed for basic research on cellulase regulation. This strain has been reported to contain a truncated carbon catabolite repressor gene cre1 and is consequently carbon catabolite derepressed. To date this and an additional frame-shift mutation in the glycoprotein-processing beta-glucosidase II encoding gene are the only known genetic differences in strain RUT C30.

Results: In the present paper we show that H. jecorina RUT C30 lacks an 85 kb genomic fragment, and consequently misses additional 29 genes comprising transcription factors, enzymes of the primary metabolism and transport proteins. This loss is already present in the ancestor of RUT C30--NG 14--and seems to have occurred in a palindromic AT-rich repeat (PATRR) typically inducing chromosomal translocations, and is not linked to the cre1 locus. The mutation of the cre1 locus has specifically occurred in RUT C30. Some of the genes that are lacking in RUT C30 could be correlated with pronounced alterations in its phenotype, such as poor growth on alpha-linked oligo- and polyglucosides (loss of maltose permease), or disturbance of osmotic homeostasis.

Conclusion: Our data place a general caveat on the use of H. jecorina RUT C30 for further basic research.

Show MeSH
Related in: MedlinePlus