Clausen IG

References (6)

Title : Complete genome sequence of the industrial bacterium Bacillus licheniformis and comparisons with closely related Bacillus species - Rey_2004_Genome.Biol_5_R77
Author(s) : Rey MW , Ramaiya P , Nelson BA , Brody-Karpin SD , Zaretsky EJ , Tang M , Lopez de Leon A , Xiang H , Gusti V , Clausen IG , Olsen PB , Rasmussen MD , Andersen JT , Jorgensen PL , Larsen TS , Sorokin A , Bolotin A , Lapidus A , Galleron N , Ehrlich SD , Berka RM
Ref : Genome Biol , 5 :R77 , 2004
Abstract : BACKGROUND: Bacillus licheniformis is a Gram-positive, spore-forming soil bacterium that is used in the biotechnology industry to manufacture enzymes, antibiotics, biochemicals and consumer products. This species is closely related to the well studied model organism Bacillus subtilis, and produces an assortment of extracellular enzymes that may contribute to nutrient cycling in nature.
RESULTS: We determined the complete nucleotide sequence of the B. licheniformis ATCC 14580 genome which comprises a circular chromosome of 4,222,336 base-pairs (bp) containing 4,208 predicted protein-coding genes with an average size of 873 bp, seven rRNA operons, and 72 tRNA genes. The B. licheniformis chromosome contains large regions that are colinear with the genomes of B. subtilis and Bacillus halodurans, and approximately 80% of the predicted B. licheniformis coding sequences have B. subtilis orthologs.
CONCLUSIONS: Despite the unmistakable organizational similarities between the B. licheniformis and B. subtilis genomes, there are notable differences in the numbers and locations of prophages, transposable elements and a number of extracellular enzymes and secondary metabolic pathway operons that distinguish these species. Differences include a region of more than 80 kilobases (kb) that comprises a cluster of polyketide synthase genes and a second operon of 38 kb encoding plipastatin synthase enzymes that are absent in the B. licheniformis genome. The availability of a completed genome sequence for B. licheniformis should facilitate the design and construction of improved industrial strains and allow for comparative genomics and evolutionary studies within this group of Bacillaceae.
ESTHER : Rey_2004_Genome.Biol_5_R77
PubMedSearch : Rey_2004_Genome.Biol_5_R77
PubMedID: 15461803
Gene_locus related to this paper: bacld-q62u01 , bacld-Q65L73 , bacld-q62yz9 , bacld-q65dz7 , bacld-q65e02 , bacld-q65eq1 , bacld-q65fc5 , bacld-q65fg2 , bacld-q65fg3 , bacld-q65fk9 , bacld-q65ft3 , bacld-q65fw3 , bacld-q65fy2 , bacld-q65gx2 , bacld-q65hn8 , bacld-q65hr4 , bacld-q65if8 , bacld-q65iy4 , bacld-q65j72 , bacld-q65le0 , bacld-q65ly2 , bacld-q65m29 , bacld-q65mg8 , bacld-q65my7 , bacld-q65n63 , bacld-q65nk2 , bacld-q65nm7 , bacli-LICC

Title : The complete genome of the crenarchaeon Sulfolobus solfataricus P2 - She_2001_Proc.Natl.Acad.Sci.U.S.A_98_7835
Author(s) : She Q , Singh RK , Confalonieri F , Zivanovic Y , Allard G , Awayez MJ , Chan-Weiher CC , Clausen IG , Curtis BA , De Moors A , Erauso G , Fletcher C , Gordon PM , Heikamp-de Jong I , Jeffries AC , Kozera CJ , Medina N , Peng X , Thi-Ngoc HP , Redder P , Schenk ME , Theriault C , Tolstrup N , Charlebois RL , Doolittle WF , Duguet M , Gaasterland T , Garrett RA , Ragan MA , Sensen CW , Van der Oost J
Ref : Proc Natl Acad Sci U S A , 98 :7835 , 2001
Abstract : The genome of the crenarchaeon Sulfolobus solfataricus P2 contains 2,992,245 bp on a single chromosome and encodes 2,977 proteins and many RNAs. One-third of the encoded proteins have no detectable homologs in other sequenced genomes. Moreover, 40% appear to be archaeal-specific, and only 12% and 2.3% are shared exclusively with bacteria and eukarya, respectively. The genome shows a high level of plasticity with 200 diverse insertion sequence elements, many putative nonautonomous mobile elements, and evidence of integrase-mediated insertion events. There are also long clusters of regularly spaced tandem repeats. Different transfer systems are used for the uptake of inorganic and organic solutes, and a wealth of intracellular and extracellular proteases, sugar, and sulfur metabolizing enzymes are encoded, as well as enzymes of the central metabolic pathways and motility proteins. The major metabolic electron carrier is not NADH as in bacteria and eukarya but probably ferredoxin. The essential components required for DNA replication, DNA repair and recombination, the cell cycle, transcriptional initiation and translation, but not DNA folding, show a strong eukaryal character with many archaeal-specific features. The results illustrate major differences between crenarchaea and euryarchaea, especially for their DNA replication mechanism and cell cycle processes and their translational apparatus.
ESTHER : She_2001_Proc.Natl.Acad.Sci.U.S.A_98_7835
PubMedSearch : She_2001_Proc.Natl.Acad.Sci.U.S.A_98_7835
PubMedID: 11427726
Gene_locus related to this paper: sulso-APEH1 , sulso-APEH2 , sulso-APEH3 , sulso-est , sulir-f0ndq1 , sulso-lipP2 , sulso-pip , sulso-SSO1433 , sulso-SSO2262 , sulso-SSO2518 , sulso-SSO2979

Title : The role of Glu87 and Trp89 in the lid of Humicola lanuginosa lipase - Martinelle_1996_Protein.Eng_9_519
Author(s) : Martinelle M , Holmquist M , Clausen IG , Patkar S , Svendsen A , Hult K
Ref : Protein Engineering , 9 :519 , 1996
Abstract : The importance of Glu87 and Trp89 in the lid of Humicola lanuginosa lipase for the hydrolytic activity at the water/lipid interface was investigated by site-directed mutagenesis. It was found that the effect on the hydrolytic activity upon the replacement of Trp89 with Phe, Leu, Gly or Glu was substrate dependent. The Trp89 mutants displayed an altered chain length specificity towards triglycerides, with a higher relative activity towards triacetin and trioctanoin compared with tributyrin. Trp89 was shown to be less important in the hydrolysis of vinyl esters compared with ethyl esters and triglycerides. An exclusive effect on the acylation reaction rate by the mutation of Trp89 was consistent with the data. It is suggested that Trp89 is important in the process of binding the acyl chain of the substrate into the active site for optimal acylation reaction rate. The Trp89Phe mutation resulted in an increased hydrolytic activity towards 2-alkylalkanoic acid esters. This is suggested to be due to reduction of unfavourable van der Waals contacts between Trp89 and the 2-substituent of the substrate. Thus, in contrast to natural substrates, Trp89 has a negative impact on the catalytic efficiency when substrates with bulky acyl chains are used. In contrast to the Trp89 mutations, the effect on the hydrolytic activity of the Glu87Ala mutation was almost substrate independent, 35-70% activity of wild-type lipase. A reduction of both the acylation and deacylation reaction was consistent with the data.
ESTHER : Martinelle_1996_Protein.Eng_9_519
PubMedSearch : Martinelle_1996_Protein.Eng_9_519
PubMedID: 8862552
Gene_locus related to this paper: humla-1lipa

Title : Probing a functional role of Glu87 and Trp89 in the lid of Humicola lanuginosa lipase through transesterification reactions in organic solvent - Holmquist_1995_J.Protein.Chem_14_217
Author(s) : Holmquist M , Clausen IG , Patkar S , Svendsen A , Hult K
Ref : J Protein Chem , 14 :217 , 1995
Abstract : To reveal the functional role of Glu87 and Trp89 in the lid of Humicola lanuginosa lipase, site-directed mutagenesis at Glu87 and Trp89 was carried out. The catalytic performance of wild-type and mutated lipases was studied in transesterification reactions in cyclohexane at a controlled water activity. Two different acyl donors were used in the investigation: tributyrin, a natural substrate for a lipase, and vinyl butyrate, an activated ester suitable for fast and efficient lipase-catalyzed transformations in preparative organic synthesis. As acyl acceptor 1-heptanol was used. The Glu87Ala mutation decreased the Vmax,app value with tributyrin and vinyl butyrate by a factor of 1.5 and 2, respectively. The Km,app for tributyrin was not affected by the Glu87Ala mutation, but the Km,app for vinyl butyrate increased twofold compared to the wild-type lipase. Changing Trp89 into a Phe residue afforded an enzyme with a 2.7- and 2-fold decreased Vmax,app with the substrates tributyrin and vinyl butyrate, respectively, compared to the wild-type lipase. No significant effects on the Km,app values for tributyrin or vinyl butyrate were seen as a result of the Trp89Phe mutation. However, the introduction of a Glu residue at position 89 in the lid increased the Km,app for tributyrin and vinyl butyrate by a factor of > 5 and 2, respectively. The Trp89Glu mutated lipase could not be saturated with tributyrin within the experimental conditions (0-680 mM) studied here. With vinyl butyrate as a substrate the Vmax,app was only 6% of that obtained with wild-type enzyme.
ESTHER : Holmquist_1995_J.Protein.Chem_14_217
PubMedSearch : Holmquist_1995_J.Protein.Chem_14_217
PubMedID: 7662109
Gene_locus related to this paper: humla-1lipa

Title : Trp89 in the lid of Humicola lanuginosa lipase is important for efficient hydrolysis of tributyrin - Holmquist_1994_Lipids_29_599
Author(s) : Holmquist M , Martinelle M , Clausen IG , Patkar S , Svendsen A , Hult K
Ref : Lipids , 29 :599 , 1994
Abstract : To determine whether Trp89 located in the lid of the lipase (EC from Humicola lanuginosa is important for the catalytic property of the enzyme, site-directed mutagenesis at Trp89 was carried out. The kinetic properties of wild type and mutated enzymes were studied with tributyrin as substrate. Lipase variants in which Trp89 was changed to Phe, Leu, Gly or Glu all showed less than 14% of the activity compared to that of the wild type lipase. The Trp89Glu mutant was the least active with only 1% of the activity seen with the wild type enzyme. All Trp mutants had the same binding affinity to the tributyrin substrate interface as did the wild type enzyme. Wild type lipase showed saturation kinetics against tributyrin when activities were measured with mixed emulsions containing different proportions of tributyrin and the nonionic alkyl polyoxyethylene ether surfactant, Triton DF-16. Wild type enzyme showed a Vmax = 6000 +/- 300 mmol.min-1.g-1 and an apparent Km = 16 +/- 2% (vol/vol) for tributyrin in Triton DF-16, while the mutants did not show saturation kinetics in an identical assay. The apparent Km for tributyrin in Triton DF-16 was increased as the result of replacing Trp89 with other residues (Phe, Leu, Gly or Glu). The activities of all mutants were more sensitive to the presence of Triton DF-16 in the tributyrin substrate than was wild type lipase. The activity of the Trp89Glu mutant was decreased to 50% in the presence of 2 vol% Triton DF-16 compared to the activity seen with pure tributyrin as substrate.(ABSTRACT TRUNCATED AT 250 WORDS)
ESTHER : Holmquist_1994_Lipids_29_599
PubMedSearch : Holmquist_1994_Lipids_29_599
PubMedID: 7815893
Gene_locus related to this paper: humla-1lipa

Title : Lipases from Rhizomucor miehei and Humicola lanuginosa: modification of the lid covering the active site alters enantioselectivity - Holmquist_1993_J.Protein.Chem_12_749
Author(s) : Holmquist M , Martinelle M , Berglund P , Clausen IG , Patkar S , Svendsen A , Hult K
Ref : J Protein Chem , 12 :749 , 1993
Abstract : The homologous lipases from Rhizomucor miehei and Humicola lanuginosa showed approximately the same enantioselectivity when 2-methyldecanoic acid esters were used as substrates. Both lipases preferentially hydrolyzed the S-enantiomer of 1-heptyl 2-methyldecanoate (R. miehei: ES = 8.5; H. lanuginosa: ES = 10.5), but the R-enantiomer of phenyl 2-methyldecanoate (ER = 2.9). Chemical arginine specific modification of the R. miehei lipase with 1,2-cyclohexanedione resulted in a decreased enantioselectivity (ER = 2.0), only when the phenyl ester was used as a substrate. In contrast, treatment with phenylglyoxal showed a decreased enantioselectivity (ES = 2.5) only when the heptyl ester was used as a substrate. The presence of guanidine, an arginine side chain analog, decreased the enantioselectivity with the heptyl ester (ES = 1.9) and increased the enantioselectivity with the aromatic ester (ER = 4.4) as substrates. The mutation, Glu 87 Ala, in the lid of the H. lanuginosa lipase, which might decrease the electrostatic stabilization of the open-lid conformation of the lipase, resulted in 47% activity compared to the native lipase, in a tributyrin assay. The Glu 87 Ala mutant showed an increased enantioselectivity with the heptyl ester (ES = 17.4) and a decreased enantioselectivity with the phenyl ester (ER = 2.5) as substrates, compared to native lipase. The enantioselectivities of both lipases in the esterification of 2-methyldecanoic acid with 1-heptanol were unaffected by the lid modifications.
ESTHER : Holmquist_1993_J.Protein.Chem_12_749
PubMedSearch : Holmquist_1993_J.Protein.Chem_12_749
PubMedID: 8136025