Structural studies on some enterobacterial capsular antigens
- Authors: Whittaker, Darryl Vanstone
- Date: 1994
- Subjects: Bacterial antigens -- Analysis Antigens Enterobacteriaceae Escherichia coli Klebsiella
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3803 , http://hdl.handle.net/10962/d1003281
- Description: The investigations presented in this thesis form part of a systematic international effort to establish the structures of the capsules produced by the bacterial genera, Escherichia coli and Klebsiella (family enterobacteriaceae). These bacteria are of medical interest as they are opportunistic pathogens and are frequently responsible for serious infections in animals and man. Invasive strains are invariably surrounded by a structurally complex polysaccharide capsule which contributes to the organism's ability to attenuate non-specific host defence mechanisms or, in some instances, to completely prevent an immune response. A knowledge of the chemical composition and structure of the capsule is, therefore, of great value as it provides insight into the mechanisms involved in this process. The E. coli, in particular, have generated considerable interest as their capsules are more structurally diverse and cross-reactivity with other, more pathogenic bacteria has also been demonstrated. Accordingly, the structures of three previously unstudied E. coli K-antigens viz. those produced by serotypes 020:K83:H26, 020:K84:H26, and 09:K48:H9 have been established by chemical and spectroscopic means and are presented in this thesis. In addition, a reinvestigation of the structure of the capsule produced by Klebsiella K15 using a novel enzymatic approach was also undertaken and a revised structure is proposed . The E. coli K48 polysaccharide is of special interest as it was found to contain a new diacetamido trideoxy hexose hitherto unrecorded. A synthesis for this saccharide is also presented. Finally, the application of lithium dissolved in ethylenediamine for the degradation of amino sugar-containing polysaccharides was also investigated using the capsular polysaccharides produced by E. coli serotypes K38 and K84 as model compounds.
- Full Text:
- Date Issued: 1994
- Authors: Whittaker, Darryl Vanstone
- Date: 1994
- Subjects: Bacterial antigens -- Analysis Antigens Enterobacteriaceae Escherichia coli Klebsiella
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3803 , http://hdl.handle.net/10962/d1003281
- Description: The investigations presented in this thesis form part of a systematic international effort to establish the structures of the capsules produced by the bacterial genera, Escherichia coli and Klebsiella (family enterobacteriaceae). These bacteria are of medical interest as they are opportunistic pathogens and are frequently responsible for serious infections in animals and man. Invasive strains are invariably surrounded by a structurally complex polysaccharide capsule which contributes to the organism's ability to attenuate non-specific host defence mechanisms or, in some instances, to completely prevent an immune response. A knowledge of the chemical composition and structure of the capsule is, therefore, of great value as it provides insight into the mechanisms involved in this process. The E. coli, in particular, have generated considerable interest as their capsules are more structurally diverse and cross-reactivity with other, more pathogenic bacteria has also been demonstrated. Accordingly, the structures of three previously unstudied E. coli K-antigens viz. those produced by serotypes 020:K83:H26, 020:K84:H26, and 09:K48:H9 have been established by chemical and spectroscopic means and are presented in this thesis. In addition, a reinvestigation of the structure of the capsule produced by Klebsiella K15 using a novel enzymatic approach was also undertaken and a revised structure is proposed . The E. coli K48 polysaccharide is of special interest as it was found to contain a new diacetamido trideoxy hexose hitherto unrecorded. A synthesis for this saccharide is also presented. Finally, the application of lithium dissolved in ethylenediamine for the degradation of amino sugar-containing polysaccharides was also investigated using the capsular polysaccharides produced by E. coli serotypes K38 and K84 as model compounds.
- Full Text:
- Date Issued: 1994
Chemical and spectroscopic studies of the capsular polysaccharides of some klebsiella and escherichia coli serotypes
- Authors: Stanley, Shawn Mark Ross
- Date: 1990
- Subjects: Polysaccharides , Klebsiella , Escherichia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3736 , http://hdl.handle.net/10962/d1001525
- Description: The work described in this thesis forms part of an international programme concerned with the structure elucidation of the capsular antigens of some Enterobacteriaceae. Many of the Klebsiella and some of the Escherichia coli are pathogenic to man and, hence, they are of interest. The virulence of bacteria is a multifactorial phenomenon, in which characteristic traits of bacteria and their hosts play comparable and complementary roles. It is accepted that pathogens are more virulent when encapsulated, because, nearly all disease causing bacteria have a capsule when freshly isolated from the host. This increase in pathogenicity is related, in part, to the capsular polysaccharides' ability to avoid or attenuate the host defence mechanisms. In the majority of cases the protective aspects of the capsule are overcome in the latter stages of infection when the formation of specific antibodies by the host has occurred. However there are situations in which an immune state of the infected host is virtually never reached, and susceptiblity to the infecting bacteria is maintained even in the advanced stage of an infection. Explanation of this phenomenon becomes possible by analysing the structure of the polysaccharides. The inability of the host to raise an immune response to the capsule may be because the structure of the polysaccharide is similar or identical to the host's carbohydrates. The serological and pathogenic relatedness of encapsulated E. coli and Klebsiella, to the encapsulated strains of other genera, is based on structural identity or similarity of the respective capsules. Capsular polysaccharides are analysed by both chemical and instrumental methods, and, at present, nuclear magnetic resonance spectroscopy is the most important analytical technique
- Full Text:
- Date Issued: 1990
- Authors: Stanley, Shawn Mark Ross
- Date: 1990
- Subjects: Polysaccharides , Klebsiella , Escherichia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3736 , http://hdl.handle.net/10962/d1001525
- Description: The work described in this thesis forms part of an international programme concerned with the structure elucidation of the capsular antigens of some Enterobacteriaceae. Many of the Klebsiella and some of the Escherichia coli are pathogenic to man and, hence, they are of interest. The virulence of bacteria is a multifactorial phenomenon, in which characteristic traits of bacteria and their hosts play comparable and complementary roles. It is accepted that pathogens are more virulent when encapsulated, because, nearly all disease causing bacteria have a capsule when freshly isolated from the host. This increase in pathogenicity is related, in part, to the capsular polysaccharides' ability to avoid or attenuate the host defence mechanisms. In the majority of cases the protective aspects of the capsule are overcome in the latter stages of infection when the formation of specific antibodies by the host has occurred. However there are situations in which an immune state of the infected host is virtually never reached, and susceptiblity to the infecting bacteria is maintained even in the advanced stage of an infection. Explanation of this phenomenon becomes possible by analysing the structure of the polysaccharides. The inability of the host to raise an immune response to the capsule may be because the structure of the polysaccharide is similar or identical to the host's carbohydrates. The serological and pathogenic relatedness of encapsulated E. coli and Klebsiella, to the encapsulated strains of other genera, is based on structural identity or similarity of the respective capsules. Capsular polysaccharides are analysed by both chemical and instrumental methods, and, at present, nuclear magnetic resonance spectroscopy is the most important analytical technique
- Full Text:
- Date Issued: 1990
Structural studies on some capsular antigens from escherichia coli and klebsiella
- Authors: Anderson, Andrew Nixon
- Date: 1988
- Subjects: Escherichia , Klebsiella , Antigens
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3730 , http://hdl.handle.net/10962/d1001469
- Description: A review of the structural studies of bacterial capsular polysaccharides (K-antigens) from Escherichia coli and Klebsiella, and of the trends in modern chemical and instrumental techniques available for the analysis of carbohydrate material is presented. The structural elucidations of the capsular polysaccharides from E. coli K37 and K55, and Klebsiella K39 are reported with comments on the novelty and possible immunological significance of the structures. The usefulness of the bacteriophage degradation technique has been emphasized using the polysaccharides from E. coli K55, and Klebsiella K30 and K39 to demonstrate the scope of the reaction
- Full Text:
- Date Issued: 1988
- Authors: Anderson, Andrew Nixon
- Date: 1988
- Subjects: Escherichia , Klebsiella , Antigens
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3730 , http://hdl.handle.net/10962/d1001469
- Description: A review of the structural studies of bacterial capsular polysaccharides (K-antigens) from Escherichia coli and Klebsiella, and of the trends in modern chemical and instrumental techniques available for the analysis of carbohydrate material is presented. The structural elucidations of the capsular polysaccharides from E. coli K37 and K55, and Klebsiella K39 are reported with comments on the novelty and possible immunological significance of the structures. The usefulness of the bacteriophage degradation technique has been emphasized using the polysaccharides from E. coli K55, and Klebsiella K30 and K39 to demonstrate the scope of the reaction
- Full Text:
- Date Issued: 1988
Reaction of carbohydrates with the sulphuryl chloride-N, N-dimethyl formamide reagent
- Authors: Mabusela, Wilfred Thozamile
- Date: 1982
- Subjects: Chemical reactions Carbohydrates
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3731 , http://hdl.handle.net/10962/d1001470
- Description: An investigation of the reaction of the sulphuryl chloride-N, N-dimethyl formamide reagent with several carbohydrate compounds, containing free hydroxyl groups, was undertaken, mainly with the view of looking at substitution of the hydroxyl groups with chlorine atoms. The reaction was found to lead to substitution of both primary and secondary hydroxyl groups with chlorine, with inversion of configuration in the latter case. The reagent was further found to effect formylation and chlorosulphation of secondary hydroxyl groups, where nucleophilic substitution by a chlorine was not favourable. Studies involving the methyl pentopyranosides, showed that the reagent was particularly useful in the chlorosulphation and chlorination of sugars, compared with the hexopyranosides.
- Full Text:
- Date Issued: 1982
- Authors: Mabusela, Wilfred Thozamile
- Date: 1982
- Subjects: Chemical reactions Carbohydrates
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3731 , http://hdl.handle.net/10962/d1001470
- Description: An investigation of the reaction of the sulphuryl chloride-N, N-dimethyl formamide reagent with several carbohydrate compounds, containing free hydroxyl groups, was undertaken, mainly with the view of looking at substitution of the hydroxyl groups with chlorine atoms. The reaction was found to lead to substitution of both primary and secondary hydroxyl groups with chlorine, with inversion of configuration in the latter case. The reagent was further found to effect formylation and chlorosulphation of secondary hydroxyl groups, where nucleophilic substitution by a chlorine was not favourable. Studies involving the methyl pentopyranosides, showed that the reagent was particularly useful in the chlorosulphation and chlorination of sugars, compared with the hexopyranosides.
- Full Text:
- Date Issued: 1982
Synthesis and reactions of sugar chlorosulphates
- Authors: Glass, Beverley Dawn
- Date: 1982
- Subjects: Chemical reactions Sugar -- Synthesis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3826 , http://hdl.handle.net/10962/d1006145
- Description: Summary: Partially chlorosulphated derivatives were synthesised for the purpose of examining the reactions of the chlorosulphonyloxy group in the presence of free hydroxyl groups. The behaviour of the chlorosulphonyloxy group was investigated under acidic conditions. Since sterically favoured chlorosulphonyloxy groups undergo facile replacement by chlorine to form chlorodeoxy sugars, some compounds possessing chlorosulphonyloxy groups which,due to polar and steric effects are not replaced by chloride,were investigated with a view to possible activation of the unfavourable centres towards nucleophilic substitution, thereby making available previously inaccessible chlorodeoxy sugars.
- Full Text:
- Date Issued: 1982
- Authors: Glass, Beverley Dawn
- Date: 1982
- Subjects: Chemical reactions Sugar -- Synthesis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3826 , http://hdl.handle.net/10962/d1006145
- Description: Summary: Partially chlorosulphated derivatives were synthesised for the purpose of examining the reactions of the chlorosulphonyloxy group in the presence of free hydroxyl groups. The behaviour of the chlorosulphonyloxy group was investigated under acidic conditions. Since sterically favoured chlorosulphonyloxy groups undergo facile replacement by chlorine to form chlorodeoxy sugars, some compounds possessing chlorosulphonyloxy groups which,due to polar and steric effects are not replaced by chloride,were investigated with a view to possible activation of the unfavourable centres towards nucleophilic substitution, thereby making available previously inaccessible chlorodeoxy sugars.
- Full Text:
- Date Issued: 1982
The polysaccharides of Opuntia ficus-indica (L.) Mill. and Opuntia aurantiaca Lindl.
- Authors: McGarvie, Donald
- Date: 1977
- Subjects: Polysaccharides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4438 , http://hdl.handle.net/10962/d1007597
- Description: The partially acetylated acidic mucilage isolated from the cactus Opuntia ficus-indica consists of a highly branched molecule containing D-galactose, L-arabinose, D-xylose, D-galacturonic acid and L-rhamnose in the ratio 2.9:6.6:3.8:1.3 : 1.0. A partial hydrolysis study led to the isolation of fourteen oligosaccharides and a degraded polysaccharide. Periodate oxidation of the degraded polysaccharide and methylation analysis of the degraded and reduced degraded polysaccharides led to the proposal of a structure for the degraded polysaccharide consisting of a chain of alternating α-l,4-D-galactopyranosyluronic acid and β-1,2-Lrhamnopyranosyl units with branches consisting of short chains of β-1,6-D-galactopyranosyl units Iinked to C-3 of the rhamnose residues. An insight into the nature of the peripheral side-chains was obtained by methylation studies of the oligosaccharides and the native polysaccharide. The majority of the side-chains are terminated by D-xylopyranosyl and L-arabinofuranosyl units while there is a small proportion of D-galactopyranosyl end-groups. The remaining units of the peripheral chains consists of mainly 1,3- and 1,5-1 inked L-arabinofuranosyl units. The acidic polysaccharide isolated from the jointed cactus Opuntia aurantiaca contains D-galactose, L-arabinose, D-xylose, D-galacturonic acid and L-rhamnose in the ratio 5.9:5 .5:3.4: 1. 2:1.0 . A partial hydrolysis study revealed a similar series of galactose containing oligosaccharides as was identified from the mucilage of Opuntia ficus-indica. The degraded polysaccharide isolated from the partial hydrolysate was methylated and a possible structure proposed for the repeating unit. Methylation studies of the native polysaccharide indicated a polysaccharide with a more complex structure than that for the mucilage of Opuntia ficus-indica.
- Full Text:
- Date Issued: 1977
- Authors: McGarvie, Donald
- Date: 1977
- Subjects: Polysaccharides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4438 , http://hdl.handle.net/10962/d1007597
- Description: The partially acetylated acidic mucilage isolated from the cactus Opuntia ficus-indica consists of a highly branched molecule containing D-galactose, L-arabinose, D-xylose, D-galacturonic acid and L-rhamnose in the ratio 2.9:6.6:3.8:1.3 : 1.0. A partial hydrolysis study led to the isolation of fourteen oligosaccharides and a degraded polysaccharide. Periodate oxidation of the degraded polysaccharide and methylation analysis of the degraded and reduced degraded polysaccharides led to the proposal of a structure for the degraded polysaccharide consisting of a chain of alternating α-l,4-D-galactopyranosyluronic acid and β-1,2-Lrhamnopyranosyl units with branches consisting of short chains of β-1,6-D-galactopyranosyl units Iinked to C-3 of the rhamnose residues. An insight into the nature of the peripheral side-chains was obtained by methylation studies of the oligosaccharides and the native polysaccharide. The majority of the side-chains are terminated by D-xylopyranosyl and L-arabinofuranosyl units while there is a small proportion of D-galactopyranosyl end-groups. The remaining units of the peripheral chains consists of mainly 1,3- and 1,5-1 inked L-arabinofuranosyl units. The acidic polysaccharide isolated from the jointed cactus Opuntia aurantiaca contains D-galactose, L-arabinose, D-xylose, D-galacturonic acid and L-rhamnose in the ratio 5.9:5 .5:3.4: 1. 2:1.0 . A partial hydrolysis study revealed a similar series of galactose containing oligosaccharides as was identified from the mucilage of Opuntia ficus-indica. The degraded polysaccharide isolated from the partial hydrolysate was methylated and a possible structure proposed for the repeating unit. Methylation studies of the native polysaccharide indicated a polysaccharide with a more complex structure than that for the mucilage of Opuntia ficus-indica.
- Full Text:
- Date Issued: 1977
A structural investigation of the sulphated polysaccharide from Aeodes ulvoidea Schmitz
- Allsobrook, Anthony John Robert
- Authors: Allsobrook, Anthony John Robert
- Date: 1973
- Subjects: Red algae -- Composition Polysaccharides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4437 , http://hdl.handle.net/10962/d1007482
- Description: Aeodes ulvoidea, a red seaweed of the Grateloupiaceae, yielded a highly sulphated polysaccharide which was shown to contain D- and L-galactose, 4-0-methy-L-galactose, 2-0-methyl - D- and L-galactose and 6-0-methyl-D-galactose, together with chromatographic traces of xylose and mannose. The sulphate was not labile to alkali, but it was largely removed with methanolic hydrogen chloride. Periodate oxidation of the polysaccharide, methylation of the de sulphated polysaccharide, and investigation of fifteen oligosaccharides from partial hydrolysis and acetolysis studies of the polysaccharide, indicate that (a) the polysaccharide is composed of a backbone of D-galactose residues which are 1,3- and 1,4-linked (b) at least some regions of alternating structure do occur (c) the 2-0-methylgalactose is linked through the 4-position (d) the 4-0-methyl-L-galactose is present as single unit side chains glycosidically linked to the galactose backbone at position 6, and (e) most of the 6-0-methyl-D-galactose is linked to the 4-position of 2-0-methyl-D-galactose.
- Full Text:
- Date Issued: 1973
- Authors: Allsobrook, Anthony John Robert
- Date: 1973
- Subjects: Red algae -- Composition Polysaccharides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4437 , http://hdl.handle.net/10962/d1007482
- Description: Aeodes ulvoidea, a red seaweed of the Grateloupiaceae, yielded a highly sulphated polysaccharide which was shown to contain D- and L-galactose, 4-0-methy-L-galactose, 2-0-methyl - D- and L-galactose and 6-0-methyl-D-galactose, together with chromatographic traces of xylose and mannose. The sulphate was not labile to alkali, but it was largely removed with methanolic hydrogen chloride. Periodate oxidation of the polysaccharide, methylation of the de sulphated polysaccharide, and investigation of fifteen oligosaccharides from partial hydrolysis and acetolysis studies of the polysaccharide, indicate that (a) the polysaccharide is composed of a backbone of D-galactose residues which are 1,3- and 1,4-linked (b) at least some regions of alternating structure do occur (c) the 2-0-methylgalactose is linked through the 4-position (d) the 4-0-methyl-L-galactose is present as single unit side chains glycosidically linked to the galactose backbone at position 6, and (e) most of the 6-0-methyl-D-galactose is linked to the 4-position of 2-0-methyl-D-galactose.
- Full Text:
- Date Issued: 1973
A structural investigation of the sulphated polysaccharide of Anathaca dentata (suhr) papenf. and the xylan of Chaetangium erinaceum (turn.) papenf.
- Authors: Russell, Irina
- Date: 1972
- Subjects: Polysaccharides , Marine algae -- Composition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4494 , http://hdl.handle.net/10962/d1013103
- Description: Hot-water extraction of Anatheca dentata, a red seaweed belonging to the family Solieriaceae, yielded a mixture of polysaccharides. Fractionation of this mixture with Cetavlon gave a glucomannan as minor component and a highly sulphated major component, which gave D- and L-galactose, D-xylose and small amounts of 3-0 (underscore)-methylgalactose, pyruvic acid and uronic acid on hydrolysis. All subsequent investigations were carried out on the sulphated major component. The sulphate was not labile to alkali, but was removed with methanolic hydrogen chloride. Periodate oxidation of the polysaccharide before and after desulphation indicated that new a-glycol groups were formed during desulphation. All the xylose units in the polymer were cleaved by periodate and this, together with the fact that the major xylose product from methylation analysis of the desulphated polymer was the 2,3, 4-tri-0 (underscore)-methyl derivative, indicated that the xylose occurs as a non-reducing end-group. Methylation of the desulphated polysaccharide revealed the presence of 1,4- and 1,3- linked D- galactose and 1,4- linked L-galactose units in the polymer. D-Glucuronic acid occurred as non-reducing end-groups. Summary, p. 1.
- Full Text:
- Date Issued: 1972
- Authors: Russell, Irina
- Date: 1972
- Subjects: Polysaccharides , Marine algae -- Composition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4494 , http://hdl.handle.net/10962/d1013103
- Description: Hot-water extraction of Anatheca dentata, a red seaweed belonging to the family Solieriaceae, yielded a mixture of polysaccharides. Fractionation of this mixture with Cetavlon gave a glucomannan as minor component and a highly sulphated major component, which gave D- and L-galactose, D-xylose and small amounts of 3-0 (underscore)-methylgalactose, pyruvic acid and uronic acid on hydrolysis. All subsequent investigations were carried out on the sulphated major component. The sulphate was not labile to alkali, but was removed with methanolic hydrogen chloride. Periodate oxidation of the polysaccharide before and after desulphation indicated that new a-glycol groups were formed during desulphation. All the xylose units in the polymer were cleaved by periodate and this, together with the fact that the major xylose product from methylation analysis of the desulphated polymer was the 2,3, 4-tri-0 (underscore)-methyl derivative, indicated that the xylose occurs as a non-reducing end-group. Methylation of the desulphated polysaccharide revealed the presence of 1,4- and 1,3- linked D- galactose and 1,4- linked L-galactose units in the polymer. D-Glucuronic acid occurred as non-reducing end-groups. Summary, p. 1.
- Full Text:
- Date Issued: 1972
A structural investigation of the sulphated polysaccharide pachymenia carnos (J. Ag.) J. Ag.
- Authors: Farrant, Annette J
- Date: 1972
- Subjects: Polysaccharides Red algae -- Composition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4470 , http://hdl.handle.net/10962/d1011785
- Description: The highly sulphated, methylated polysaccharide isolated from Pachymenia Carnosa, a red seaweed, was shown to contain D- galactose, 2-o (underscore) methyl-D- galactose, 6-o (underscore) -methyl- D- galactose and 4-o (underscore)-methylgalactose. The polysaccharide was desulphated with methanolic hydrogen chloride. Methylation of the desulphated polysaccharide revealed that it was composed entirely of (1→73) and (1→4) links in approximately equal amounts. Treatment of the polysaccharide with alkali showed that the majority of the ester sulphate groups were alkali-stable. Partial hydrolysis and acetolysis studies indicated that the polysaccharide was extremely complex, and contained alternate (1→3) and β (1→4) glycosidic linkages. There is evidence for the presence of D-galactose-6-sulphate.
- Full Text:
- Date Issued: 1972
- Authors: Farrant, Annette J
- Date: 1972
- Subjects: Polysaccharides Red algae -- Composition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4470 , http://hdl.handle.net/10962/d1011785
- Description: The highly sulphated, methylated polysaccharide isolated from Pachymenia Carnosa, a red seaweed, was shown to contain D- galactose, 2-o (underscore) methyl-D- galactose, 6-o (underscore) -methyl- D- galactose and 4-o (underscore)-methylgalactose. The polysaccharide was desulphated with methanolic hydrogen chloride. Methylation of the desulphated polysaccharide revealed that it was composed entirely of (1→73) and (1→4) links in approximately equal amounts. Treatment of the polysaccharide with alkali showed that the majority of the ester sulphate groups were alkali-stable. Partial hydrolysis and acetolysis studies indicated that the polysaccharide was extremely complex, and contained alternate (1→3) and β (1→4) glycosidic linkages. There is evidence for the presence of D-galactose-6-sulphate.
- Full Text:
- Date Issued: 1972
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