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The Chlorophyll-Proteins of Soybean (Glycine max L. var. Wayne) Cotyledons')
Short Communication
The Chlorophyll-Proteins of Soybean (Glycine max L. yare Wayne) Cotyledonsl) TERRY M. BRICKER2) and DAVID W. NEWMAN Department of Botany, Miami University, Oxford, Ohio 45056 (U.S.A.) Received May 5, 1981 . Accepted May 25, 1981
Summary The chlorophyll-proteins of chloroplasts isolated from soybean cotyledons were examined. Ten chlorophyll-proteins were observed and nine of these were characterized with respect to visible absorption spectra, relative mobility, relative % distribution, chlorophyll alb ratio, and the presence or absence of room temperature fluorescence. Three P -700 chlorophyll-a protein complexes (CP 1, CP la, and CP lb), including one previously unreported (CP lb), were resolved. CP lb has a visible absorption spectrum and room temperature fluorescence characteristics identical to that of CP la but possesses a higher mobility, migrating between CP 1 and CP la. Four light-harvesting chlorophyll alb protein complexes (HCp O- LHCP3) and two chlorophyll-a proteins (CPal, CPa2; possible reaction centers for PS II) were observed. In general, the characteristics of these chlorophyll-proteins are very similar to those isolated from barley chloroplasts. Additionally, a simple method for extracting chlorophyll from polyacrylamide gel slices is described. Key words: Glycine max, chlorophyll·proteins, SDS·PAGE.
Introduction While the chlorophyll-proteins of various algae and the leaves of many higher plants have been extensively investigated (Thornber et al. 1979), those of other green, non-leafy organs have been largely ignored. The cotyledons of soybean (Glycine max L. var. Wayne) are green and photosynthetically active. Their chloroplasts exhibit an extensive granal and intergranal thylakoid pattern typical of C 3 and some C 4 chloroplasts (Huber and Newman 1976; Tuquet and Newman 1980). Greening of the cotyledons takes place rapidly, beginning prior to the emergence of the epicotyl, maximum chlorophyll being accumulated before the emergence of the primary leaves. Chlorophyll content reaches its maximum between days six and ten (post-planting) and thereafter decreases rapidly, the cotyledons yellowing and abscising by day thirty (Dalgarn and Newman, unpublished observations).
1) Supported in part by a grant from Sigma Xi. 2) Current address: University of Missouri, Division of Biological Sciences, Tucker Hall, Columbia, MO. 65211, USA.
z. Pjlanzenphysiol. Bd.
104. S. 91 - 96. 1981.
92
TERRY M. BRICKER and DAVID W. NEWMAN
Numerous chlorophyll-binding proteins have been described since Thornber's et
al. (1966) original observations. In the highest resolving systems as many as ten chlorophyll-binding proteins have been characterized (Machold et al. 1979). Unfortunately, the precise nature and function of the majority of these have not been elucidated. In this communication the chlorophyll-proteins isolated from the chloroplasts of soybean cotyledons will be examined. Additionally, a simple method for the extraction of chlorophyll from polyacrylamide gel sections and a previously unreported P -700 chlorophyll-a protein complex will be described. Materials and Methods Soybeans were grown under conditions previously described (Bricker and Newman 19S0). Cotyledons from eight d (postplanting) soybeans were used in this study. Chloroplasts were isolated from ten gram lots of cotyledons by grinding at high speed in a blender with 30 ml of an isolation media (Kannangara et al. 1973). The resultant brei was filtered through two layers of Miracloth (Calbiochem Co.) and centrifuged at 10,000 xg for 15 min. The chloroplast pellet was washed twice in 50 mM K2 HPO., 10 mM KCl, pH 7.S at 4 cC, aliquots being removed for chlorophyll determination by the method of Arnon (1949). The chloroplast thylakoids were solubilized in 50 mM tris-HCl, 0.5% SDS, 5% sucrose and 1 mM phenylmethylsulfonylfluoride, pH S.4, which was cooled immediately prior to solubilization. After suspension in this buffer, the mixture was immediately centrifuged at 40,000 xg for 15 min. No chlorophyll was found in the resulting pellet. The final SDS: chlorophyll ratio was 20 : 1; lower SDS: chlorophyll ratios did not fully solubilize the chlorophyll-proteins. Electrophoresis was performed immediately in a discontinuous buffer system (Bricker and Newman 19S0) in cylindrical polyacrylamide gels (4% stacking-S% running) at 4 cC in the dark. A current of 1 malgel for 15 min followed by 2 rna/gel for 30-45 min was supplied. Total migration distance was less than 4 em as longer electrophoretic migrations lead to the progressive loss of some of the chlorophyll-protein components (Wild et al. 19S0). The gels were removed and scanned at 650 nm and 675 nm in a Gilford spectrophotometer. The relative amount of chlorophyll in each band was estimated by integrating each peak at both wavelengths and averaging the results (Hiller et al. 1974). Visible wavelength absorption spectra were obtained from excised gel segments by grinding the segments in 50 mM tris-HCl, pH 7.9 at 4 cc, centrifuging at 10,000 x g for 10 min, and performing wavelength scans on the eluted chlorophyll-proteins with a Perkin-Elmer spectrophotometer. For chlorophyll alb ratio estimation gel segments were ground in 40% acetone at room temperature. At this acetone concentration the chlorophyll was freely elui:ed without the collapse of the polyacrylamide gel structure. The resultant slurry was brought to SO% acetone with 100% acetone at which concentration the majority of the polyacrylamide precipitates. The chlorophyll solution was further clarified by a brief centrifugation at 10,000 xg for 5 min and chlorophyll determined using Arnon's equations (1949). Alternatively, the method of Wild et al. (19S0) was used. The gels were photographed under both visible and long-wave ultraviolet light.
Results and Discussion
Eleven chlorophyll-containing bands are resolved in this system (Figure 1). Six of these correspond to bands previously described by Anderson et al. (1978). Using Anderson's nomenclature these are: CP 1 and CP la, P -700 chlorophyll a protein Z. Pjlanzenphysiol. Bd. 104. S. 91- 96. 1981.
The chlorophyll-proteins of soybean cotyledons
UV
93
VIS CPlo CPlb
CPl
LHCpS ?
LHCpl ·LHCp2 CPa I CPol
LlfCp3
Fig. 1: Unstained polyacrylamide gels of the separated chlorophyll-proteins photographed under ultraviolet (UV) and visible (VIS) li!}ht. Apparent band splitting in UV image of LHCP is due to selfabsorption. UV fluorescence of CPa1 and LHCp2 is readily visible in original gels.
FC
complexes; LHCp l , LHCP2 , and LHCP 3, light-harvesting chlorophyll alb protein complexes; and free chlorophyll. Additionally, two bands were located in the position of Anderson's CPa, the possible reaction center of PS II. These have been designated CPal and CPa2 and possess identical visible absorption spectra (Figure 2 a), and have similar chlorophyll alb ratios (Table 1). Resolution of CPa into two bands has been previously reported (Delepelaine and Chua 1979; Machold et al. 1980; Remy and Hoarau 1978) although its significance has not been established. Three additional bands which Anderson et al. (1978) do not resolve are also observed. The first of these is located between CP 1 and CP la, is non-fluorescent at room temperature, and exhibits the same visible absorption spectrum as CP la (Figure 2 a); Z. Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
94
TERRY M. BRICKER and DAVID W. NEWMAN
Table 1: The chlorophyll-proteins of soybean cotyledon chloroplasts. Chlorophyllprotein
Relative mobility
% distribution
Chlorophyll alb ratio
CPla CPlb CPl LHCp0
0.012 0.033 0.069 0.113 0.155 0.191 0.223 0.277 0.307 0.451 1.000
14.0 6.2 9.2 2.9 4.0 13.2 1.1 4.1 5.5 23.9 21.4
3.1 6.2 3.5 1.7 1.6 1.4
LHCP' LHCP 2 CPal CPa2 LHCP 3 FC
1.1
6.5 7.7 1.4 3.5
Room temperature fluorescence
+ + + + + + + +
this has been designated CP 1b. This chlorophyll-protein has not been previously described and possibly represents CP la which has been stripped of certain peripheral polypeptides. This band appears as a shoulder on the CPla peak in Anderson's et al. (1978) system. Other workers have reported additional P -700 chlorophyll a protein complexes (Remy and Hoarau 1978; Machold et al. 1979) but these are of lower mobility than CP la. 446
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\CP1a,CP1b CPa1,CPa2
LHCP1
L-.----._~=__j;;;;;::::4==:::,~~CP1 FC------~r--,--_r--.---._-,--, LHCPIIf 400
450 500 550 600 650 700
400 450 500 550 600 650 700
Wavelength (nm) Fig. 2: a) Visible absorption spectra of the chlorophyll a containing chlorophyll-proteins. b) Visible absorption spectra of the chlorophyll alb containing chlorophyll-proteins.
Z. Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
The chlorophyll-proteins of soybean cotyledons
95
Two chlorophyll-containing bands are found between CP 1 and LHCpl. The slower migrating of the two has a low chlorophyll alb ratio, and a visible absorption spectrum similar to the LHCPs (Figure 2 b); this has been designated LHCp o and corresponds to Machold's et al. (1980) Chla/b-P2>~>~*. The other, faster migrating, band has a low chlorophyll alb ratio, suggesting that it may be a LHCP complex, but is present in insufficient quantities to obtain a visible absorption spectrum and has not been named, although it probably corresponds to Machold's et al. (1980) slowest migrating Chl-P band. In Table 1 the % distribution, chlorophyll alb ratios, and room temperature fluorescence of the observed chlorophyll-proteins have been summarized. The chlorophyll-proteins associated with the PS I reaction center (CP 1, CP Ia and CP 1b) account for 34.8% of the protein-bound chlorophyll. Those associated with the PS II antenna (LHCpO, LHCpl, LHCp2, and LHCp3) account for 48.8% of the proteinbound chlorophyll, with those associated with the possible reaction center of PS II (CPa 1 and CPa2) accounting for 11.4% of the protein-bound chlorophyll. CPI, CPIa, and CPIb all exhibit the absence of room temperature fluorescence under long-wave ultraviolet excitation and possess relatively high chlorophyll alb ratios. The other observed chlorophyll-proteins are highly fluorescent at room temperature, those associated with the PS II antenna having low alb ratios while those associated with the possible PS II reaction center exhibit high chlorophyll alb ratios. Also in Table 1 are the relative mobilities of the various chlorophyll-proteins. «Molecular weights» have not been derived from these relative mobilities as the chlorophyll-proteins are not fully dissociated and, therefore, would yield seriously underestimated weights if compared to fully dissociated standard proteins. Additionally, chlorophyll-proteins yield anomalous Ferguson plots when electrophoresed in gels of different polyacrylamide concentration (Chua and Gillham 1977; Chua et al. 1975). Figures 2 a and 2 b show the room temperature absorption spectra for the observed chlorophyll-proteins. Spectra obtained for LHCP\ LHCP2 , and LHCP 3 are very similar to those obtained from barley (Anderson et al. 1978; Machold et al. 1980). LHCp o, however, exhibits a significant blue-shift of its wavelength maxima. The visible absorption spectra of CPai and CPa2 are identical, suggesting that while these two species differ in relative mobility the chlorophyll environment is unaltered. The same observation can be made of CP Ia and CP 1b. The visible absorption spectra of these components are also very similar to those found in barley. The chlorophyll-proteins derived from the chloroplasts of soybean cotyledons, therefore, appear to be virtually identical to those described in the most widely studied system, i. e., barley leaf tissue, in number, relative distribution, and properties of the individual chlorophyll-proteins. Additionally, the electrophoretic system described yields results similar to those obtained in the highest resolution systems available while being of more simple design.
Z. Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
96
TERRY M. BRICKER and DAVID W. NEWMAN
References ANDERSON, J. M., J. c. WALDRON, and S. W. THORNE: FEBS Lett. 92, 227 (1978). ARNON, D. I.: Plant Physiol. 24, 1 (1949). BRICKER, T. M. and D. W. NEWMAN: Zeit. Pflanzenphysiol. 98,339 (1980). CHUA, N.-H. and N. W. GILLHAM: J. Cell BioI. 74,441 (1977). CHUA, N.-H., K. MATLIN, and P. BENNOUN: J. Cell BioI. 67, 361 (1975). DELEPELAINE, P. and N.-H. CHUA: Nat. Acad. Sci. USA 76,111 (1979). HILLER, R. G., S. GENGE, and D. PILGER: Plant Sci. Lett. 2, 239 (1974). HUBER, D. J. and D. W. NEWMAN: J. Exp. Bot. 27, 490 (1976). KANNANGARA, C. G., B. S. JACOBSON, and P. K. STUMPF: Plant Physiol. 52, 156 (1973). MACHOLD, 0., D. J. SIMPSON, and B. L. M0LLER: Carls. Res. Comm. 44,235 (1979). REMY, R. and J. HOARAU: In: AKOYUNOGLOU et al. (Eds.): Chloroplast Development, 235 - 240. Elsevier/North Holland Press, Amsterdam, 1978. THORNBER, J. P., J. P. MARKWELL, and S. REINMAN: Photochem. Photo bioI. 29, 1205 (1979). THORNBER, J. P., C. A. SMITH, and J. L. BAILEY: Biochem. J. 100, 14 p. (1966). TUQUET, C. and D. W. NEWMAN: Cytobios 29, 43 (1980). WILD, A., B. KREBS, and W. RUHLE: Zeit. Pflanzenphysiol. 100, 1 (1980).
Z.
Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
The Chlorophyll-Proteins of Soybean (Glycine max L. yare Wayne) Cotyledonsl) TERRY M. BRICKER2) and DAVID W. NEWMAN Department of Botany, Miami University, Oxford, Ohio 45056 (U.S.A.) Received May 5, 1981 . Accepted May 25, 1981
Summary The chlorophyll-proteins of chloroplasts isolated from soybean cotyledons were examined. Ten chlorophyll-proteins were observed and nine of these were characterized with respect to visible absorption spectra, relative mobility, relative % distribution, chlorophyll alb ratio, and the presence or absence of room temperature fluorescence. Three P -700 chlorophyll-a protein complexes (CP 1, CP la, and CP lb), including one previously unreported (CP lb), were resolved. CP lb has a visible absorption spectrum and room temperature fluorescence characteristics identical to that of CP la but possesses a higher mobility, migrating between CP 1 and CP la. Four light-harvesting chlorophyll alb protein complexes (HCp O- LHCP3) and two chlorophyll-a proteins (CPal, CPa2; possible reaction centers for PS II) were observed. In general, the characteristics of these chlorophyll-proteins are very similar to those isolated from barley chloroplasts. Additionally, a simple method for extracting chlorophyll from polyacrylamide gel slices is described. Key words: Glycine max, chlorophyll·proteins, SDS·PAGE.
Introduction While the chlorophyll-proteins of various algae and the leaves of many higher plants have been extensively investigated (Thornber et al. 1979), those of other green, non-leafy organs have been largely ignored. The cotyledons of soybean (Glycine max L. var. Wayne) are green and photosynthetically active. Their chloroplasts exhibit an extensive granal and intergranal thylakoid pattern typical of C 3 and some C 4 chloroplasts (Huber and Newman 1976; Tuquet and Newman 1980). Greening of the cotyledons takes place rapidly, beginning prior to the emergence of the epicotyl, maximum chlorophyll being accumulated before the emergence of the primary leaves. Chlorophyll content reaches its maximum between days six and ten (post-planting) and thereafter decreases rapidly, the cotyledons yellowing and abscising by day thirty (Dalgarn and Newman, unpublished observations).
1) Supported in part by a grant from Sigma Xi. 2) Current address: University of Missouri, Division of Biological Sciences, Tucker Hall, Columbia, MO. 65211, USA.
z. Pjlanzenphysiol. Bd.
104. S. 91 - 96. 1981.
92
TERRY M. BRICKER and DAVID W. NEWMAN
Numerous chlorophyll-binding proteins have been described since Thornber's et
al. (1966) original observations. In the highest resolving systems as many as ten chlorophyll-binding proteins have been characterized (Machold et al. 1979). Unfortunately, the precise nature and function of the majority of these have not been elucidated. In this communication the chlorophyll-proteins isolated from the chloroplasts of soybean cotyledons will be examined. Additionally, a simple method for the extraction of chlorophyll from polyacrylamide gel sections and a previously unreported P -700 chlorophyll-a protein complex will be described. Materials and Methods Soybeans were grown under conditions previously described (Bricker and Newman 19S0). Cotyledons from eight d (postplanting) soybeans were used in this study. Chloroplasts were isolated from ten gram lots of cotyledons by grinding at high speed in a blender with 30 ml of an isolation media (Kannangara et al. 1973). The resultant brei was filtered through two layers of Miracloth (Calbiochem Co.) and centrifuged at 10,000 xg for 15 min. The chloroplast pellet was washed twice in 50 mM K2 HPO., 10 mM KCl, pH 7.S at 4 cC, aliquots being removed for chlorophyll determination by the method of Arnon (1949). The chloroplast thylakoids were solubilized in 50 mM tris-HCl, 0.5% SDS, 5% sucrose and 1 mM phenylmethylsulfonylfluoride, pH S.4, which was cooled immediately prior to solubilization. After suspension in this buffer, the mixture was immediately centrifuged at 40,000 xg for 15 min. No chlorophyll was found in the resulting pellet. The final SDS: chlorophyll ratio was 20 : 1; lower SDS: chlorophyll ratios did not fully solubilize the chlorophyll-proteins. Electrophoresis was performed immediately in a discontinuous buffer system (Bricker and Newman 19S0) in cylindrical polyacrylamide gels (4% stacking-S% running) at 4 cC in the dark. A current of 1 malgel for 15 min followed by 2 rna/gel for 30-45 min was supplied. Total migration distance was less than 4 em as longer electrophoretic migrations lead to the progressive loss of some of the chlorophyll-protein components (Wild et al. 19S0). The gels were removed and scanned at 650 nm and 675 nm in a Gilford spectrophotometer. The relative amount of chlorophyll in each band was estimated by integrating each peak at both wavelengths and averaging the results (Hiller et al. 1974). Visible wavelength absorption spectra were obtained from excised gel segments by grinding the segments in 50 mM tris-HCl, pH 7.9 at 4 cc, centrifuging at 10,000 x g for 10 min, and performing wavelength scans on the eluted chlorophyll-proteins with a Perkin-Elmer spectrophotometer. For chlorophyll alb ratio estimation gel segments were ground in 40% acetone at room temperature. At this acetone concentration the chlorophyll was freely elui:ed without the collapse of the polyacrylamide gel structure. The resultant slurry was brought to SO% acetone with 100% acetone at which concentration the majority of the polyacrylamide precipitates. The chlorophyll solution was further clarified by a brief centrifugation at 10,000 xg for 5 min and chlorophyll determined using Arnon's equations (1949). Alternatively, the method of Wild et al. (19S0) was used. The gels were photographed under both visible and long-wave ultraviolet light.
Results and Discussion
Eleven chlorophyll-containing bands are resolved in this system (Figure 1). Six of these correspond to bands previously described by Anderson et al. (1978). Using Anderson's nomenclature these are: CP 1 and CP la, P -700 chlorophyll a protein Z. Pjlanzenphysiol. Bd. 104. S. 91- 96. 1981.
The chlorophyll-proteins of soybean cotyledons
UV
93
VIS CPlo CPlb
CPl
LHCpS ?
LHCpl ·LHCp2 CPa I CPol
LlfCp3
Fig. 1: Unstained polyacrylamide gels of the separated chlorophyll-proteins photographed under ultraviolet (UV) and visible (VIS) li!}ht. Apparent band splitting in UV image of LHCP is due to selfabsorption. UV fluorescence of CPa1 and LHCp2 is readily visible in original gels.
FC
complexes; LHCp l , LHCP2 , and LHCP 3, light-harvesting chlorophyll alb protein complexes; and free chlorophyll. Additionally, two bands were located in the position of Anderson's CPa, the possible reaction center of PS II. These have been designated CPal and CPa2 and possess identical visible absorption spectra (Figure 2 a), and have similar chlorophyll alb ratios (Table 1). Resolution of CPa into two bands has been previously reported (Delepelaine and Chua 1979; Machold et al. 1980; Remy and Hoarau 1978) although its significance has not been established. Three additional bands which Anderson et al. (1978) do not resolve are also observed. The first of these is located between CP 1 and CP la, is non-fluorescent at room temperature, and exhibits the same visible absorption spectrum as CP la (Figure 2 a); Z. Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
94
TERRY M. BRICKER and DAVID W. NEWMAN
Table 1: The chlorophyll-proteins of soybean cotyledon chloroplasts. Chlorophyllprotein
Relative mobility
% distribution
Chlorophyll alb ratio
CPla CPlb CPl LHCp0
0.012 0.033 0.069 0.113 0.155 0.191 0.223 0.277 0.307 0.451 1.000
14.0 6.2 9.2 2.9 4.0 13.2 1.1 4.1 5.5 23.9 21.4
3.1 6.2 3.5 1.7 1.6 1.4
LHCP' LHCP 2 CPal CPa2 LHCP 3 FC
1.1
6.5 7.7 1.4 3.5
Room temperature fluorescence
+ + + + + + + +
this has been designated CP 1b. This chlorophyll-protein has not been previously described and possibly represents CP la which has been stripped of certain peripheral polypeptides. This band appears as a shoulder on the CPla peak in Anderson's et al. (1978) system. Other workers have reported additional P -700 chlorophyll a protein complexes (Remy and Hoarau 1978; Machold et al. 1979) but these are of lower mobility than CP la. 446
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\CP1a,CP1b CPa1,CPa2
LHCP1
L-.----._~=__j;;;;;::::4==:::,~~CP1 FC------~r--,--_r--.---._-,--, LHCPIIf 400
450 500 550 600 650 700
400 450 500 550 600 650 700
Wavelength (nm) Fig. 2: a) Visible absorption spectra of the chlorophyll a containing chlorophyll-proteins. b) Visible absorption spectra of the chlorophyll alb containing chlorophyll-proteins.
Z. Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
The chlorophyll-proteins of soybean cotyledons
95
Two chlorophyll-containing bands are found between CP 1 and LHCpl. The slower migrating of the two has a low chlorophyll alb ratio, and a visible absorption spectrum similar to the LHCPs (Figure 2 b); this has been designated LHCp o and corresponds to Machold's et al. (1980) Chla/b-P2>~>~*. The other, faster migrating, band has a low chlorophyll alb ratio, suggesting that it may be a LHCP complex, but is present in insufficient quantities to obtain a visible absorption spectrum and has not been named, although it probably corresponds to Machold's et al. (1980) slowest migrating Chl-P band. In Table 1 the % distribution, chlorophyll alb ratios, and room temperature fluorescence of the observed chlorophyll-proteins have been summarized. The chlorophyll-proteins associated with the PS I reaction center (CP 1, CP Ia and CP 1b) account for 34.8% of the protein-bound chlorophyll. Those associated with the PS II antenna (LHCpO, LHCpl, LHCp2, and LHCp3) account for 48.8% of the proteinbound chlorophyll, with those associated with the possible reaction center of PS II (CPa 1 and CPa2) accounting for 11.4% of the protein-bound chlorophyll. CPI, CPIa, and CPIb all exhibit the absence of room temperature fluorescence under long-wave ultraviolet excitation and possess relatively high chlorophyll alb ratios. The other observed chlorophyll-proteins are highly fluorescent at room temperature, those associated with the PS II antenna having low alb ratios while those associated with the possible PS II reaction center exhibit high chlorophyll alb ratios. Also in Table 1 are the relative mobilities of the various chlorophyll-proteins. «Molecular weights» have not been derived from these relative mobilities as the chlorophyll-proteins are not fully dissociated and, therefore, would yield seriously underestimated weights if compared to fully dissociated standard proteins. Additionally, chlorophyll-proteins yield anomalous Ferguson plots when electrophoresed in gels of different polyacrylamide concentration (Chua and Gillham 1977; Chua et al. 1975). Figures 2 a and 2 b show the room temperature absorption spectra for the observed chlorophyll-proteins. Spectra obtained for LHCP\ LHCP2 , and LHCP 3 are very similar to those obtained from barley (Anderson et al. 1978; Machold et al. 1980). LHCp o, however, exhibits a significant blue-shift of its wavelength maxima. The visible absorption spectra of CPai and CPa2 are identical, suggesting that while these two species differ in relative mobility the chlorophyll environment is unaltered. The same observation can be made of CP Ia and CP 1b. The visible absorption spectra of these components are also very similar to those found in barley. The chlorophyll-proteins derived from the chloroplasts of soybean cotyledons, therefore, appear to be virtually identical to those described in the most widely studied system, i. e., barley leaf tissue, in number, relative distribution, and properties of the individual chlorophyll-proteins. Additionally, the electrophoretic system described yields results similar to those obtained in the highest resolution systems available while being of more simple design.
Z. Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.
96
TERRY M. BRICKER and DAVID W. NEWMAN
References ANDERSON, J. M., J. c. WALDRON, and S. W. THORNE: FEBS Lett. 92, 227 (1978). ARNON, D. I.: Plant Physiol. 24, 1 (1949). BRICKER, T. M. and D. W. NEWMAN: Zeit. Pflanzenphysiol. 98,339 (1980). CHUA, N.-H. and N. W. GILLHAM: J. Cell BioI. 74,441 (1977). CHUA, N.-H., K. MATLIN, and P. BENNOUN: J. Cell BioI. 67, 361 (1975). DELEPELAINE, P. and N.-H. CHUA: Nat. Acad. Sci. USA 76,111 (1979). HILLER, R. G., S. GENGE, and D. PILGER: Plant Sci. Lett. 2, 239 (1974). HUBER, D. J. and D. W. NEWMAN: J. Exp. Bot. 27, 490 (1976). KANNANGARA, C. G., B. S. JACOBSON, and P. K. STUMPF: Plant Physiol. 52, 156 (1973). MACHOLD, 0., D. J. SIMPSON, and B. L. M0LLER: Carls. Res. Comm. 44,235 (1979). REMY, R. and J. HOARAU: In: AKOYUNOGLOU et al. (Eds.): Chloroplast Development, 235 - 240. Elsevier/North Holland Press, Amsterdam, 1978. THORNBER, J. P., J. P. MARKWELL, and S. REINMAN: Photochem. Photo bioI. 29, 1205 (1979). THORNBER, J. P., C. A. SMITH, and J. L. BAILEY: Biochem. J. 100, 14 p. (1966). TUQUET, C. and D. W. NEWMAN: Cytobios 29, 43 (1980). WILD, A., B. KREBS, and W. RUHLE: Zeit. Pflanzenphysiol. 100, 1 (1980).
Z.
Pjlanzenphysiol. Bd. 104. S. 91-96. 1981.