Score: 2.00 | Title: P instability factor : an active maize transposon system associated with the amplification of Tourist-like MITEs and a new superfamily of transposases .
| Author: Zhang X Feschotte C Zhang Q Jiang N Eggleston WB Wessler SR .
| Journal: Proc . Natl . Acad . Sci . USA Citation: V : 98 ( 22 ) P : 12572-7 Year: 2001 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11675493 Accession (PMID): 11675493 | Abstract: Miniature inverted-repeat transposable elements ( MITEs ) are widespread and abundant in both plant and animal genomes .
Despite the discovery and characterization of many MITE families , their origin and transposition mechanism are still poorly understood , largely because MITEs are nonautonomous elements with no coding capacity .
The starting point for this study was P instability factor ( PIF ) , an active DNA transposable element family from maize that was first identified following multiple mutagenic insertions into exactly the same site in intron 2 of the maize anthocyanin regulatory gene R In this study we report the isolation of a maize Tourist-like MITE family called miniature PIF ( mPIF ) that shares several features with PIF elements , including identical terminal inverted repeats , similar subterminal sequences , and an unusual but striking preference for an extended 9-bp target site .
These shared features indicate that mPIF and PIF elements were amplified by the same or a closely related transposase .
This transposase was identified through the isolation of several PIF elements and the identification of one element ( called PIFa ) that cosegregated with PIF activity .
PIFa encodes a putative protein with homologs in Arabidopsis , rice , sorghum , nematodes , and a fungus .
Our data suggest that PIFa and these PIF-like elements belong to a new eukaryotic DNA transposon superfamily that is distantly related to the bacterial IS5 group and are responsible for the origin and spread of Tourist-like MITEs .
| Matching Sentences: [ Sen. 3, subscore: 1.00 ]: Miniature inverted-repeat transposable elements ( MITEs ) are widespread and abundant in both plant and animal genomes . Despite the discovery and characterization of many MITE families , their origin and transposition mechanism are still poorly understood , largely because MITEs are nonautonomous elements with no coding capacity . The starting point for this study was P instability factor ( PIF ) , an active DNA transposable element family from maize that was first identified following multiple mutagenic insertions into exactly the same site in intron 2 of the maize anthocyanin regulatory gene R In this study we report the isolation of a maize Tourist-like MITE family called miniature PIF ( mPIF ) that shares several features with PIF elements , including identical terminal inverted repeats , similar subterminal sequences , and an unusual but striking preference for an extended 9-bp target site . These shared features indicate that mPIF and PIF elements were amplified by the same or a closely related transposase . This transposase was identified through the isolation of several PIF elements and the identification of one element ( called PIFa ) that cosegregated with PIF activity . PIFa encodes a putative protein with homologs in Arabidopsis , rice , sorghum , nematodes , and a fungus . Our data suggest that PIFa and these PIF-like elements belong to a new eukaryotic DNA transposon superfamily that is distantly related to the bacterial IS5 group and are responsible for the origin and spread of Tourist-like MITEs . [ Sen. 4, subscore: 1.00 ]: Miniature inverted-repeat transposable elements ( MITEs ) are widespread and abundant in both plant and animal genomes . Despite the discovery and characterization of many MITE families , their origin and transposition mechanism are still poorly understood , largely because MITEs are nonautonomous elements with no coding capacity . The starting point for this study was P instability factor ( PIF ) , an active DNA transposable element family from maize that was first identified following multiple mutagenic insertions into exactly the same site in intron 2 of the maize anthocyanin regulatory gene R In this study we report the isolation of a maize Tourist-like MITE family called miniature PIF ( mPIF ) that shares several features with PIF elements , including identical terminal inverted repeats , similar subterminal sequences , and an unusual but striking preference for an extended 9-bp target site . These shared features indicate that mPIF and PIF elements were amplified by the same or a closely related transposase . This transposase was identified through the isolation of several PIF elements and the identification of one element ( called PIFa ) that cosegregated with PIF activity . PIFa encodes a putative protein with homologs in Arabidopsis , rice , sorghum , nematodes , and a fungus . Our data suggest that PIFa and these PIF-like elements belong to a new eukaryotic DNA transposon superfamily that is distantly related to the bacterial IS5 group and are responsible for the origin and spread of Tourist-like MITEs .
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Score: 4.00 | Title: An active DNA transposon family in rice .
| Author: Jiang N Bao Z Zhang X Hirochika H Eddy SR McCouch SR Wessler SR .
| Journal: Nature Citation: V : 421 ( 6919 ) P : 163-7 Year: 2003 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12520302 Accession (PMID): 12520302 | Abstract: The publication of draft sequences for the two subspecies of Oryza sativa ( rice ) , japonica ( cv .
Nipponbare ) and indica ( cv .
93-11 ) , provides a unique opportunity to study the dynamics of transposable elements in this important crop plant .
Here we report the use of these sequences in a computational approach to identify the first active DNA transposons from rice and the first active miniature inverted-repeat transposable element ( MITE ) from any organism .
A sequence classified as a Tourist-like MITE of 430 base pairs , called miniature Ping ( mPing ) , was present in about 70 copies in Nipponbare and in about 14 copies in 93-11 .
These mPing elements , which are all nearly identical , transpose actively in an indica cell-culture line .
Database searches identified a family of related transposase-encoding elements ( called Pong ) , which also transpose actively in the same cells .
Virtually all new insertions of mPing and Pong elements were into low-copy regions of the rice genome .
Since the domestication of rice mPing MITEs have been amplified preferentially in cultivars adapted to environmental extremes-a situation that is reminiscent of the genomic shock theory for transposon activation . | Matching Sentences: [ Sen. 5, subscore: 1.00 ]: The publication of draft sequences for the two subspecies of Oryza sativa ( rice ) , japonica ( cv . Nipponbare ) and indica ( cv . 93-11 ) , provides a unique opportunity to study the dynamics of transposable elements in this important crop plant . Here we report the use of these sequences in a computational approach to identify the first active DNA transposons from rice and the first active miniature inverted-repeat transposable element ( MITE ) from any organism . A sequence classified as a Tourist-like MITE of 430 base pairs , called miniature Ping ( mPing ) , was present in about 70 copies in Nipponbare and in about 14 copies in 93-11 . These mPing elements , which are all nearly identical , transpose actively in an indica cell-culture line . Database searches identified a family of related transposase-encoding elements ( called Pong ) , which also transpose actively in the same cells . Virtually all new insertions of mPing and Pong elements were into low-copy regions of the rice genome . Since the domestication of rice mPing MITEs have been amplified preferentially in cultivars adapted to environmental extremes-a situation that is reminiscent of the genomic shock theory for transposon activation . [ Sen. 6, subscore: 1.00 ]: Nipponbare ) and indica ( cv . 93-11 ) , provides a unique opportunity to study the dynamics of transposable elements in this important crop plant . Here we report the use of these sequences in a computational approach to identify the first active DNA transposons from rice and the first active miniature inverted-repeat transposable element ( MITE ) from any organism . A sequence classified as a Tourist-like MITE of 430 base pairs , called miniature Ping ( mPing ) , was present in about 70 copies in Nipponbare and in about 14 copies in 93-11 . These mPing elements , which are all nearly identical , transpose actively in an indica cell-culture line . Database searches identified a family of related transposase-encoding elements ( called Pong ) , which also transpose actively in the same cells . Virtually all new insertions of mPing and Pong elements were into low-copy regions of the rice genome . Since the domestication of rice mPing MITEs have been amplified preferentially in cultivars adapted to environmental extremes-a situation that is reminiscent of the genomic shock theory for transposon activation . [ Sen. 8, subscore: 1.00 ]: Here we report the use of these sequences in a computational approach to identify the first active DNA transposons from rice and the first active miniature inverted-repeat transposable element ( MITE ) from any organism . A sequence classified as a Tourist-like MITE of 430 base pairs , called miniature Ping ( mPing ) , was present in about 70 copies in Nipponbare and in about 14 copies in 93-11 . These mPing elements , which are all nearly identical , transpose actively in an indica cell-culture line . Database searches identified a family of related transposase-encoding elements ( called Pong ) , which also transpose actively in the same cells . Virtually all new insertions of mPing and Pong elements were into low-copy regions of the rice genome . Since the domestication of rice mPing MITEs have been amplified preferentially in cultivars adapted to environmental extremes-a situation that is reminiscent of the genomic shock theory for transposon activation . [ Sen. 9, subscore: 1.00 ]: A sequence classified as a Tourist-like MITE of 430 base pairs , called miniature Ping ( mPing ) , was present in about 70 copies in Nipponbare and in about 14 copies in 93-11 . These mPing elements , which are all nearly identical , transpose actively in an indica cell-culture line . Database searches identified a family of related transposase-encoding elements ( called Pong ) , which also transpose actively in the same cells . Virtually all new insertions of mPing and Pong elements were into low-copy regions of the rice genome . Since the domestication of rice mPing MITEs have been amplified preferentially in cultivars adapted to environmental extremes-a situation that is reminiscent of the genomic shock theory for transposon activation .
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Score: 3.00 | Title: The plant MITE mPing is mobilized in anther culture .
| Author: Kikuchi K Terauchi K Wada M Hirano HY .
| Journal: Nature Citation: V : 421 ( 6919 ) P : 167-70 Year: 2003 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub12520303 Accession (PMID): 12520303 | Abstract: Transposable elements constitute a large portion of eukaryotic genomes and contribute to their evolution and diversification .
Miniature inverted-repeat transposable elements ( MITEs ) constitute one of the main groups of transposable elements and are distributed ubiquitously in the genomes of plants and animals such as maize , rice , Arabidopsis , human , insect and nematode .
Because active MITEs have not been identified , the transposition mechanism of MITEs and their accumulation in eukaryotic genomes remain poorly understood .
Here we describe a new class of MITE , called miniature Ping ( mPing ) , in the genome of Oryza sativa ( rice ) . mPing elements are activated in cells derived from anther culture , where they are excised efficiently from original sites and reinserted into new loci .
An mPing-associated Ping element , which has a putative PIF family transposase , is implicated in the recent proliferation of this MITE family in a subspecies of rice . | Matching Sentences: [ Sen. 4, subscore: 2.00 ]: Transposable elements constitute a large portion of eukaryotic genomes and contribute to their evolution and diversification . Miniature inverted-repeat transposable elements ( MITEs ) constitute one of the main groups of transposable elements and are distributed ubiquitously in the genomes of plants and animals such as maize , rice , Arabidopsis , human , insect and nematode . Because active MITEs have not been identified , the transposition mechanism of MITEs and their accumulation in eukaryotic genomes remain poorly understood . Here we describe a new class of MITE , called miniature Ping ( mPing ) , in the genome of Oryza sativa ( rice ) . mPing elements are activated in cells derived from anther culture , where they are excised efficiently from original sites and reinserted into new loci . An mPing-associated Ping element , which has a putative PIF family transposase , is implicated in the recent proliferation of this MITE family in a subspecies of rice . [ Sen. 5, subscore: 1.00 ]: Transposable elements constitute a large portion of eukaryotic genomes and contribute to their evolution and diversification . Miniature inverted-repeat transposable elements ( MITEs ) constitute one of the main groups of transposable elements and are distributed ubiquitously in the genomes of plants and animals such as maize , rice , Arabidopsis , human , insect and nematode . Because active MITEs have not been identified , the transposition mechanism of MITEs and their accumulation in eukaryotic genomes remain poorly understood . Here we describe a new class of MITE , called miniature Ping ( mPing ) , in the genome of Oryza sativa ( rice ) . mPing elements are activated in cells derived from anther culture , where they are excised efficiently from original sites and reinserted into new loci . An mPing-associated Ping element , which has a putative PIF family transposase , is implicated in the recent proliferation of this MITE family in a subspecies of rice .
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Score: 15.00 | Title: Purification and characterization of a high molecular mass serine carboxypeptidase from Monascus pilosus .
| Author: Liu F Tachibana S Taira T Ishihara M Kato F Yasuda M | Journal: J Ind . Microbiol . Biotechnol . Citation: V : 31 ( 12 ) P : 572-80 Year: 2004 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15592905 Accession (PMID): 15592905 | Abstract: Two serine carboxypeptidases , MpiCP-1 and MpiCP-2 , were purified to homogeneity from Monascus pilosus IFO 4480 .
MpiCP-1 is a homodimer with a native molecular mass of 125 kDa composed of two identical subunits of 61 kDa , while MpiCP-2 is a high mass homooligomer with a native molecular mass of 2 , 263 kDa composed of about 38 identical subunits of 59 kDa .
This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase .
The two purified enzymes were both acidic glycoproteins .
MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively .
The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 .
MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 .
Phenylmethylsulfonylfluoride strongly inhibited MpiCP-1 and completely inhibited MpiCP-2 , suggesting that they are both serine carboxypeptidases .
Of the substrates tested , benzyloxycarbonyl-L : -tyrosyl-L : -glutamic acid ( Z-Tyr-Glu ) was the best for both enzymes .
The Km , Vmax , Kcat and Kcat/Km values of MpiCP-1 for Z-Tyr-Glu at pH 4 . 0 and 37 degrees C were 1 . 33 mM , 1 . 49 mM min ( -1 ) , 723 s ( -1 ) and 545 mM ( -1 ) s ( -1 ) , and those of MpiCP-2 at pH 3 . 5 and 37 degrees C were 1 . 55 mM , 1 . 54 mM min ( -1 ) , 2 , 039 s ( -1 ) and 1 , 318 mM ( -1 ) s ( -1 ) , respectively . | Matching Sentences: [ Sen. 1, subscore: 2.00 ]: Two serine carboxypeptidases , MpiCP-1 and MpiCP-2 , were purified to homogeneity from Monascus pilosus IFO 4480 . MpiCP-1 is a homodimer with a native molecular mass of 125 kDa composed of two identical subunits of 61 kDa , while MpiCP-2 is a high mass homooligomer with a native molecular mass of 2 , 263 kDa composed of about 38 identical subunits of 59 kDa . This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase . The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . [ Sen. 2, subscore: 2.00 ]: Two serine carboxypeptidases , MpiCP-1 and MpiCP-2 , were purified to homogeneity from Monascus pilosus IFO 4480 . MpiCP-1 is a homodimer with a native molecular mass of 125 kDa composed of two identical subunits of 61 kDa , while MpiCP-2 is a high mass homooligomer with a native molecular mass of 2 , 263 kDa composed of about 38 identical subunits of 59 kDa . This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase . The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . [ Sen. 5, subscore: 2.00 ]: Two serine carboxypeptidases , MpiCP-1 and MpiCP-2 , were purified to homogeneity from Monascus pilosus IFO 4480 . MpiCP-1 is a homodimer with a native molecular mass of 125 kDa composed of two identical subunits of 61 kDa , while MpiCP-2 is a high mass homooligomer with a native molecular mass of 2 , 263 kDa composed of about 38 identical subunits of 59 kDa . This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase . The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 . Phenylmethylsulfonylfluoride strongly inhibited MpiCP-1 and completely inhibited MpiCP-2 , suggesting that they are both serine carboxypeptidases . Of the substrates tested , benzyloxycarbonyl-L : -tyrosyl-L : -glutamic acid ( Z-Tyr-Glu ) was the best for both enzymes . [ Sen. 6, subscore: 2.00 ]: MpiCP-1 is a homodimer with a native molecular mass of 125 kDa composed of two identical subunits of 61 kDa , while MpiCP-2 is a high mass homooligomer with a native molecular mass of 2 , 263 kDa composed of about 38 identical subunits of 59 kDa . This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase . The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 . Phenylmethylsulfonylfluoride strongly inhibited MpiCP-1 and completely inhibited MpiCP-2 , suggesting that they are both serine carboxypeptidases . Of the substrates tested , benzyloxycarbonyl-L : -tyrosyl-L : -glutamic acid ( Z-Tyr-Glu ) was the best for both enzymes . The Km , Vmax , Kcat and Kcat/Km values of MpiCP-1 for Z-Tyr-Glu at pH 4 . 0 and 37 degrees C were 1 . 33 mM , 1 . 49 mM min ( -1 ) , 723 s ( -1 ) and 545 mM ( -1 ) s ( -1 ) , and those of MpiCP-2 at pH 3 . 5 and 37 degrees C were 1 . 55 mM , 1 . 54 mM min ( -1 ) , 2 , 039 s ( -1 ) and 1 , 318 mM ( -1 ) s ( -1 ) , respectively . [ Sen. 7, subscore: 2.00 ]: This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase . The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 . Phenylmethylsulfonylfluoride strongly inhibited MpiCP-1 and completely inhibited MpiCP-2 , suggesting that they are both serine carboxypeptidases . Of the substrates tested , benzyloxycarbonyl-L : -tyrosyl-L : -glutamic acid ( Z-Tyr-Glu ) was the best for both enzymes . The Km , Vmax , Kcat and Kcat/Km values of MpiCP-1 for Z-Tyr-Glu at pH 4 . 0 and 37 degrees C were 1 . 33 mM , 1 . 49 mM min ( -1 ) , 723 s ( -1 ) and 545 mM ( -1 ) s ( -1 ) , and those of MpiCP-2 at pH 3 . 5 and 37 degrees C were 1 . 55 mM , 1 . 54 mM min ( -1 ) , 2 , 039 s ( -1 ) and 1 , 318 mM ( -1 ) s ( -1 ) , respectively . [ Sen. 8, subscore: 2.00 ]: The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 . Phenylmethylsulfonylfluoride strongly inhibited MpiCP-1 and completely inhibited MpiCP-2 , suggesting that they are both serine carboxypeptidases . Of the substrates tested , benzyloxycarbonyl-L : -tyrosyl-L : -glutamic acid ( Z-Tyr-Glu ) was the best for both enzymes . The Km , Vmax , Kcat and Kcat/Km values of MpiCP-1 for Z-Tyr-Glu at pH 4 . 0 and 37 degrees C were 1 . 33 mM , 1 . 49 mM min ( -1 ) , 723 s ( -1 ) and 545 mM ( -1 ) s ( -1 ) , and those of MpiCP-2 at pH 3 . 5 and 37 degrees C were 1 . 55 mM , 1 . 54 mM min ( -1 ) , 2 , 039 s ( -1 ) and 1 , 318 mM ( -1 ) s ( -1 ) , respectively . [ Sen. 10, subscore: 2.00 ]: The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 . Phenylmethylsulfonylfluoride strongly inhibited MpiCP-1 and completely inhibited MpiCP-2 , suggesting that they are both serine carboxypeptidases . Of the substrates tested , benzyloxycarbonyl-L : -tyrosyl-L : -glutamic acid ( Z-Tyr-Glu ) was the best for both enzymes . The Km , Vmax , Kcat and Kcat/Km values of MpiCP-1 for Z-Tyr-Glu at pH 4 . 0 and 37 degrees C were 1 . 33 mM , 1 . 49 mM min ( -1 ) , 723 s ( -1 ) and 545 mM ( -1 ) s ( -1 ) , and those of MpiCP-2 at pH 3 . 5 and 37 degrees C were 1 . 55 mM , 1 . 54 mM min ( -1 ) , 2 , 039 s ( -1 ) and 1 , 318 mM ( -1 ) s ( -1 ) , respectively . [ Sen. 3, subscore: 1.00 ]: Two serine carboxypeptidases , MpiCP-1 and MpiCP-2 , were purified to homogeneity from Monascus pilosus IFO 4480 . MpiCP-1 is a homodimer with a native molecular mass of 125 kDa composed of two identical subunits of 61 kDa , while MpiCP-2 is a high mass homooligomer with a native molecular mass of 2 , 263 kDa composed of about 38 identical subunits of 59 kDa . This is unique among carboxypeptidases and distinguishes MpiCP-2 as the largest known carboxypeptidase . The two purified enzymes were both acidic glycoproteins . MpiCP-1 has an isoelectric point of 3 . 7 and a carbohydrate content of 11% , while for MpiCP-2 these values were 4 . 0 and 33% , respectively . The optimum pH and temperature were around 4 . 0 and 50 degrees C for MpiCP-1 , and 3 . 5 and 50 degrees C for MpiCP-2 . MpiCP-1 was stable over a broad range of pH between 2 . 0 and 8 . 0 at 37 degrees C for 1 h , and up to 55 degrees C for 15 min at pH 6 . 0 , but MpiCP-2 was stable in a narrow range of pH between 5 . 5 and 6 . 5 , and up to 50 degrees C for 15 min at pH 6 . 0 .
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