Microbial
Pathogenesis
Short
1990; 8: 371-375
communication
Cross-hybridization between the cytadhesin genes of M ycoplasma pneumoniae and M ycoplasma genitabum and genomic DNA of Mycoplasma gallisep Shatha
ticum
F. Dallo
and Joel B. Baseman*
Department of Microbiology, University of Texas Health Science 7703 Floyd Curl Drive, San Antonio, Texas 78284- 7758, U.S.A. (Received
November
22, 1989; accepted
in revised form February
Center at San Antonio,
22, 1990)
Dallo, S. F. (Dept of Microbiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, Texas 78284-7758, U.S.A.) and J. B. Baseman. Crosshybridization between the cytadhesin genes of Mycoplasma pneumoniae and Mycoplasma genitalium and genomic DNA of Mycoplasma gallisepticum. Microbial Pathogenesis 1990; 8: 371-375. Immunological cross-reactivity was observed between the cytadhesin proteins of Mycoplasma pneumoniae and Mycoplasma genitalium and a 155 kDa protein of Mycoplasma gallisepticum. Furthermore, the cytadhesin genes of M. pneumoniae and M. genitalium were used to demonstrate homology with M. gallisepticum genomic DNA under low stringency conditions suggesting that a family of adhesin-related genes exists among these pathogenic mycoplasmas. Key words: mycoplasma;
cytadhesin
gene; cross-hybridization.
Mycoplasma pneumoniae, Mycoplasma genitalium and Mycoplasma gallisepticum are pathogenic prokaryotes that share similar biological properties such as a flask-shape penetrate host defense appearance and adherence to host cells. ‘~3 These mycoplasmas barriers and parasitize tissues via unique differentiated tip organelles that exhibit a nap-like appearance. *-‘,* Earlier reports indicated that the adhesin proteins of M. pneumoniae and A4 genitalium, both human pathogens, cluster at the tip structures and regulate attachment and recognition of host receptors.*.‘,” The adhesin of M. pneumoniae, designated PI, is a 170 kDa trypsin-sensitive protein. Brief trypsin treatment of M. pneumoniae’j or exposure to antibodies directed against specific PI epitopes”~‘* blocks cytadherence. In M, genitalium a 140 kDa adhesin has been identified that shares crossreactive epitopes with the Pl adhesin of k? pneumoniae.13-l5 Also, extensive DNA and protein sequence homologies between these cytadhesins These similarities between the two adhesins are especially have been described.‘6m’g noteworthy because the PI gene of M. pneumoniae has an A+T content of 46.5% while the n/l. genitalium adhesin gene has an A+T content of 60.1% consistent with *Author 0882-401
to whom
correspondence
o/90/050371
+05
so3.00/0
should
be addressed @ 1990
Academic
Press
Limlted
S. F. Dallo
372
and J. B. Baseman
the preferential use of A- and T-rich codons by M. genitalium.” Also, considerable and M. genitalium differences in the G +C contents of genomic DNA of M. pneumoniae exist.” Nonetheless, the chemical and functional relatedness exhibited by the two adhesin genes and their products clearly reinforce their fundamental evolutionary importance in mycoplasma virulence. The existence of an analogue adhesin protein in M. gallisepticum, an avian pathogen, has been less cIear’3,20 although evidence suggests that a common population of receptors on red blood cells mediate adherence of these mycoplasma species.‘,‘5 In this paper we utilized several methodologies to demonstrate cytadhesin-related sequences in M. gallisepticum. Virulent M. pneumoniae strain Ml 29-816 and M. gallisepticum strain (S6) were grown in 32 oz (c. 950 ml) prescription bottles in 70 ml modified Edward medium” M. pneumoniae were washed four times with at 37°C for 72 h. Glass-adherent phosphate-buffered saline (PBS; pH 7.2) and collected by centrifugation (95OOxg, which adheres less avidly to glass, both glass-adherent 20 min). With M. gallisepticum, Mycoplasma and detached organisms were combined and washed by centrifugation. genitalium G37 was grown in SP-4 medium22,23 and similar procedures to those for M. pneumoniae were employed. M. genitalium and M. pneuTotal protein immunoreactivity of M. gallisepticum, moniae was determined by solubilizing mycoplasma pellets, separating proteins using 7.5% sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis and electrophoretically transferring the proteins to nitrocellulose paper prior to immunoblotting14 with rabbit monospecific and mouse monoclonal anti-adhesin antibodies. the 140 Cross-reactive epitopes shared by the 170 kDa Pl protein of M. pneumoniae, and a 155 kDa protein of M. gallisepticum were kDa adhesin protein of M. genitalium observed (Fig. 1) using rabbit monospecific antibody to the PI and 140 kDa proteins and M. genitalium, respectively. These molecular weight values are of M. pneumoniae and M. consistent with the gene and deduced amino acid sequences of M. genitalium pneumoniae adhesins reported by us”,” but differ considerably from the values
A
0
46-
30Fig. 1. lmmunoblot of M. pneumoniae proteins usmg M. pneumoniae anti-PI with M. genitalium anti-140 kDa antiserum.
(lane A), M. genitalium (lane B). and M. gallisepticum (lane C) rabbit monospecific antibody. Similar results were obtained Molecular weight standards in kDa are shown at the left.
Mycoplasma
cytadhesin
genes
373
published by Clyde and Hu.‘~ In addition, our estimated molecular mass of 155 kDa putative adhesin contrasts with their value of 190 kDa.13 for the M. gallisepticum Blots of these three mycoplasma strains were also reacted with cytadherenceblocking monoclonal antibodies (mAbs) generated against the Pl and 140 kDa exhibited strong proteins. As expected, mAbs to the Pl protein of M, pneumoniae reactivity against the homologous 170 kDa protein and weak reactivity against the 140 kDa protein of M. genita/ium.‘4,‘5 Likewise, mAbs to the 140 kDa protein of NI. genitalium were strongly reactive in the homologous blot and weakly reactive against Neither group of mAbs exhibited reactivity against the PI protein of M. pneumoniae. M. gallisepticum suggesting the absence of related epitopes. Since the Pl and 140 kDa genes share considerable homology at the DNA level,‘“~‘g genomic DNA. M. we examined their capacity to hybridize with M. gallisepticum gallisepticum cells were resuspended in 2.7 ml of PBS buffer, lysed by addition of 0.3 ml of 10% SDS and incubated with 50~9 RNAse (Boehringer Mannheim Biochemicals, Indiana) per ml for 30 min at 37°C. DNA preparations were extracted three times with an equal volume of phenol equilibrated with 1 M Tris (pH 8.0), once with phenol : chloroform (1 : 1 ), and once with chloroform : isoamyl alcohol (24 : 1). Sodium acetate (3 M; 0.1 volume) was added to the DNA preparation, and the DNA was DNA digested with precipitated with ethanol. Southern blots of M. gallisepticum different restriction enzymes were hybridized with 32P-labeled Pl or 140 kDa structural genes.17.” Hybridizations were performed under low stringency conditions,24 and the and M. genitalium cytadhesin genes results are shown in Fig. 2. Both M. pneumoniae displayed the same patterns of hybridization with genomic DNA of M. gallisepticum, demonstrating for the first time the genetic basis for a family of adhesin-related genes among mycoplasmas pathogenic for man and animals. To establish a direct structure-function relationship between these mycoplasma genomic DNA with the 32P-radiolabeled adhesins, we probed M. gallisepticum subclone of the Pl structural gene that encodes the 13 amino acids mediating M.
A
B
C
23.1-
9.4-
6.6-
2.32.0-
Fig. 2. Hybridization of the 32P-labeled M. pneumoniae Pl gene to M. gallisepticum genomic digested with BamHI (lane A); EcoRl (lane B); HindIll (lane C); Pstl (lane D). Identical patterns observed using the M. genitahm 140 kDa gene. Molecular weight markers in kilobases are shown left.
DNA were at the
S. F. Dallo
374
and J. B. Baseman
pneumoniae cytadherence.” This subclone hybridizes to the M. genitalium 140 kDa gene under low stringency conditions. No hybridization was detected with /VI. gallisepticum DNA suggesting that this specific region of the structural gene of M. gallisepticum differs considerably from M. pneumoniae and M. genitalium. These data are consistent with the lack of immunoreactivity using cytadherence-blocking mAbs to the Pl and 140 kDa adhesin proteins as described earlier. Further studies are needed to determine the functional role of the 155 kDa protein of M. gallisepticum in cytadherence and the extent of sequence homology shared among the cytadhesin gene family of these pathogenic mycoplasmas. This information should be useful in understanding host tissue tropism and in developing diagnostic and vaccine strategies for these pathogenic mycoplasmas.
This research was Institute of Allergy
supported in part by Public Health and Infectious Diseases. We thank
Service Rose
grant Al 18540 from Garza for her secretarial
The National assistance.
References 1 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
15.
16. 17. 18.
19. 20.
Baseman JB, Banai M, Kahane I. Sialic acid residues mediate Mycoplasma pneumoniae attachment to human and sheep erythrocytes. Infect lmmun 1982; 38: 389-91. Baseman JB, Cole RM, Krause DC, Leith DK. Molecular basis for cytadsorption of Mycoplasma pneumoniae. J Bacterial 1982; 151: 1514-22. Biberfeld G, Biberfeld P. Ultrastructural features of Mycoplasma pneumoniae. J Bacterial 1970; 102: 855-61. Boatman ES. Morphology and ultrastructure of the mycoplasmatales. In: Barile MF, Razin S, eds. The mycoplasmas. Vol. 1: cell biology. New York: Academic Press 1979; 63-l 02. Collier AM, Baseman JB. Organ culture techniques with mycoplasmas. Ann NY Acad Sci 1973; 225: 277-89. Hu PC, Collier AM, Baseman JB. Surface parasitism by Mycoplasma pneumoniae of respiratory epithelium. J Exp Med; 145: 1328-43. Tully JG, Taylor-Robinson D, Cole RM, Rose DL. A newly discovered mycoplasma in the human urogenital tract. Lancet 1981; i: 1288-91. Wilson MH. Collier AM. Ultrastructural study of Mycoplasma pneumoniae in organ culture. J Bacterial 1976; 125: 332-9. Feldner J, Gobel U, Bredt W. Mycoplasma pneumoniae adhesin localized to tip structure by monoclonal antibody. Nature 1982; 298: 765-7. Hu PC, Cole RM, Huang YS et al. Mycoplasma pneumoniae infection: role of a surface protein in the attachment organelle. Science 1982; 219: 313-315. Dallo SF, Su CJ, Horton JR, Baseman JB. Identification of PI gene domain containing epitope(s) mediating Mycoplasma pneumoniae cytadherence. J Exp Med 1988; 167: 718-23. Krause DC, Baseman JB. Inhibition of Mycoplasma pneumoniae hemadsorption and adherence to respiratory epithelium by antibodies to a membrane protein. Infect lmmun 1983; 39: 1180-86. Clyde WA Jr, Hu PC. Antigenic determinants of the attachment protein of Mycoplasma pneumoniae shared by other pathogenic Mycoplasma species. Infect lmmun 1986; 51: 690-2. Morrison-Plummer J, Jones DH, Daly K, Tully JG, Taylor-Robinson D, Baseman JB. Molecular characterization of Mycoplasma genitalium species-specific and cross-reactive determinants: identification of an immunodominant protein of M. genitalium. lsr J Med Sci 1987; 23: 453457. Morrison-Plummer J, Lazzell A, Baseman JB. Shared epitopes between Mycoplasma pneumoniae major adhesin protein Pl and a 140 kilodalton protein of Mycoplasma genitalium. Infect lmmun 1987; 55: 49-56. Dallo SF, Horton JR, Su CJ, Baseman JB. Homologous regions shared by adhesrn genes of Mycoplasma pneumoniae and Mycoplasma genitalium. Microbial Pathogenesis 1989; 6: 69-73. Dallo SF, Chavoya A, Su CJ, Baseman JB. DNA and protein sequence homologies between the adhesins of Mycoplasma genitalium and Mycoplasma pneumoniae. Infect lmmun 1989; 57: 1059-65. lnamine JM, Loechel S, Collier AM, Barile MF, Hu PC. Nucleotide sequence of MgPa (mpg) operon of Mycoplasma genitalium and comparison to the Pl (mpp) operon of Mycoplasma pneumoniae. Gene 1989; 82: 259-67. Su CJ, Tryon VV, Baseman JB. Cloning and sequence analysis of cytadhesin PI gene from Mycoplasma pneumoniae. Infect lmmun 1987; 55: 3023-g. Baseman JB, Drouillard DL, Leith D, Tully JG. Absence of Mycoplasma pneumoniae cytadsorption
Mycoplasma
21 22. 23. 24.
cytadhesin
genes
375
protein PI in Mycoplasma genitalium and Mycoplasma gallisepticum. infect lmmun 1984; 43: 11035. Edward DG. A selective medium for pleuropneumonia-like organism. J. Gen Microbial 1947; 1: 23843. Tully JG, Rose DL, Whitcomb RF, Wenzel RP. Enhanced isolation of Mycoplasma pneumoniae from throat washings with a newly modified culture medium. J Infect Dis 1979; 139: 47882. Tully JG, Whitcomb RF, Clark HF. Williamson DL. Pathogenic mycoplasmas: cultivation and vertebrate pathogenicity of a new spiroplasma. Science 1971; 195: 892-894. Wood WI, Gitschier J, Lasky LA, Lawn RM. Base composition-independent hydridization in tetramethylammonium chloride: a method for oligonucleotide screening of hrghly complex gene libraries. Proc Nat1 Acad Sci USA 1985; 82: 1585-8.
Pathogenesis
Short
1990; 8: 371-375
communication
Cross-hybridization between the cytadhesin genes of M ycoplasma pneumoniae and M ycoplasma genitabum and genomic DNA of Mycoplasma gallisep Shatha
ticum
F. Dallo
and Joel B. Baseman*
Department of Microbiology, University of Texas Health Science 7703 Floyd Curl Drive, San Antonio, Texas 78284- 7758, U.S.A. (Received
November
22, 1989; accepted
in revised form February
Center at San Antonio,
22, 1990)
Dallo, S. F. (Dept of Microbiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, Texas 78284-7758, U.S.A.) and J. B. Baseman. Crosshybridization between the cytadhesin genes of Mycoplasma pneumoniae and Mycoplasma genitalium and genomic DNA of Mycoplasma gallisepticum. Microbial Pathogenesis 1990; 8: 371-375. Immunological cross-reactivity was observed between the cytadhesin proteins of Mycoplasma pneumoniae and Mycoplasma genitalium and a 155 kDa protein of Mycoplasma gallisepticum. Furthermore, the cytadhesin genes of M. pneumoniae and M. genitalium were used to demonstrate homology with M. gallisepticum genomic DNA under low stringency conditions suggesting that a family of adhesin-related genes exists among these pathogenic mycoplasmas. Key words: mycoplasma;
cytadhesin
gene; cross-hybridization.
Mycoplasma pneumoniae, Mycoplasma genitalium and Mycoplasma gallisepticum are pathogenic prokaryotes that share similar biological properties such as a flask-shape penetrate host defense appearance and adherence to host cells. ‘~3 These mycoplasmas barriers and parasitize tissues via unique differentiated tip organelles that exhibit a nap-like appearance. *-‘,* Earlier reports indicated that the adhesin proteins of M. pneumoniae and A4 genitalium, both human pathogens, cluster at the tip structures and regulate attachment and recognition of host receptors.*.‘,” The adhesin of M. pneumoniae, designated PI, is a 170 kDa trypsin-sensitive protein. Brief trypsin treatment of M. pneumoniae’j or exposure to antibodies directed against specific PI epitopes”~‘* blocks cytadherence. In M, genitalium a 140 kDa adhesin has been identified that shares crossreactive epitopes with the Pl adhesin of k? pneumoniae.13-l5 Also, extensive DNA and protein sequence homologies between these cytadhesins These similarities between the two adhesins are especially have been described.‘6m’g noteworthy because the PI gene of M. pneumoniae has an A+T content of 46.5% while the n/l. genitalium adhesin gene has an A+T content of 60.1% consistent with *Author 0882-401
to whom
correspondence
o/90/050371
+05
so3.00/0
should
be addressed @ 1990
Academic
Press
Limlted
S. F. Dallo
372
and J. B. Baseman
the preferential use of A- and T-rich codons by M. genitalium.” Also, considerable and M. genitalium differences in the G +C contents of genomic DNA of M. pneumoniae exist.” Nonetheless, the chemical and functional relatedness exhibited by the two adhesin genes and their products clearly reinforce their fundamental evolutionary importance in mycoplasma virulence. The existence of an analogue adhesin protein in M. gallisepticum, an avian pathogen, has been less cIear’3,20 although evidence suggests that a common population of receptors on red blood cells mediate adherence of these mycoplasma species.‘,‘5 In this paper we utilized several methodologies to demonstrate cytadhesin-related sequences in M. gallisepticum. Virulent M. pneumoniae strain Ml 29-816 and M. gallisepticum strain (S6) were grown in 32 oz (c. 950 ml) prescription bottles in 70 ml modified Edward medium” M. pneumoniae were washed four times with at 37°C for 72 h. Glass-adherent phosphate-buffered saline (PBS; pH 7.2) and collected by centrifugation (95OOxg, which adheres less avidly to glass, both glass-adherent 20 min). With M. gallisepticum, Mycoplasma and detached organisms were combined and washed by centrifugation. genitalium G37 was grown in SP-4 medium22,23 and similar procedures to those for M. pneumoniae were employed. M. genitalium and M. pneuTotal protein immunoreactivity of M. gallisepticum, moniae was determined by solubilizing mycoplasma pellets, separating proteins using 7.5% sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis and electrophoretically transferring the proteins to nitrocellulose paper prior to immunoblotting14 with rabbit monospecific and mouse monoclonal anti-adhesin antibodies. the 140 Cross-reactive epitopes shared by the 170 kDa Pl protein of M. pneumoniae, and a 155 kDa protein of M. gallisepticum were kDa adhesin protein of M. genitalium observed (Fig. 1) using rabbit monospecific antibody to the PI and 140 kDa proteins and M. genitalium, respectively. These molecular weight values are of M. pneumoniae and M. consistent with the gene and deduced amino acid sequences of M. genitalium pneumoniae adhesins reported by us”,” but differ considerably from the values
A
0
46-
30Fig. 1. lmmunoblot of M. pneumoniae proteins usmg M. pneumoniae anti-PI with M. genitalium anti-140 kDa antiserum.
(lane A), M. genitalium (lane B). and M. gallisepticum (lane C) rabbit monospecific antibody. Similar results were obtained Molecular weight standards in kDa are shown at the left.
Mycoplasma
cytadhesin
genes
373
published by Clyde and Hu.‘~ In addition, our estimated molecular mass of 155 kDa putative adhesin contrasts with their value of 190 kDa.13 for the M. gallisepticum Blots of these three mycoplasma strains were also reacted with cytadherenceblocking monoclonal antibodies (mAbs) generated against the Pl and 140 kDa exhibited strong proteins. As expected, mAbs to the Pl protein of M, pneumoniae reactivity against the homologous 170 kDa protein and weak reactivity against the 140 kDa protein of M. genita/ium.‘4,‘5 Likewise, mAbs to the 140 kDa protein of NI. genitalium were strongly reactive in the homologous blot and weakly reactive against Neither group of mAbs exhibited reactivity against the PI protein of M. pneumoniae. M. gallisepticum suggesting the absence of related epitopes. Since the Pl and 140 kDa genes share considerable homology at the DNA level,‘“~‘g genomic DNA. M. we examined their capacity to hybridize with M. gallisepticum gallisepticum cells were resuspended in 2.7 ml of PBS buffer, lysed by addition of 0.3 ml of 10% SDS and incubated with 50~9 RNAse (Boehringer Mannheim Biochemicals, Indiana) per ml for 30 min at 37°C. DNA preparations were extracted three times with an equal volume of phenol equilibrated with 1 M Tris (pH 8.0), once with phenol : chloroform (1 : 1 ), and once with chloroform : isoamyl alcohol (24 : 1). Sodium acetate (3 M; 0.1 volume) was added to the DNA preparation, and the DNA was DNA digested with precipitated with ethanol. Southern blots of M. gallisepticum different restriction enzymes were hybridized with 32P-labeled Pl or 140 kDa structural genes.17.” Hybridizations were performed under low stringency conditions,24 and the and M. genitalium cytadhesin genes results are shown in Fig. 2. Both M. pneumoniae displayed the same patterns of hybridization with genomic DNA of M. gallisepticum, demonstrating for the first time the genetic basis for a family of adhesin-related genes among mycoplasmas pathogenic for man and animals. To establish a direct structure-function relationship between these mycoplasma genomic DNA with the 32P-radiolabeled adhesins, we probed M. gallisepticum subclone of the Pl structural gene that encodes the 13 amino acids mediating M.
A
B
C
23.1-
9.4-
6.6-
2.32.0-
Fig. 2. Hybridization of the 32P-labeled M. pneumoniae Pl gene to M. gallisepticum genomic digested with BamHI (lane A); EcoRl (lane B); HindIll (lane C); Pstl (lane D). Identical patterns observed using the M. genitahm 140 kDa gene. Molecular weight markers in kilobases are shown left.
DNA were at the
S. F. Dallo
374
and J. B. Baseman
pneumoniae cytadherence.” This subclone hybridizes to the M. genitalium 140 kDa gene under low stringency conditions. No hybridization was detected with /VI. gallisepticum DNA suggesting that this specific region of the structural gene of M. gallisepticum differs considerably from M. pneumoniae and M. genitalium. These data are consistent with the lack of immunoreactivity using cytadherence-blocking mAbs to the Pl and 140 kDa adhesin proteins as described earlier. Further studies are needed to determine the functional role of the 155 kDa protein of M. gallisepticum in cytadherence and the extent of sequence homology shared among the cytadhesin gene family of these pathogenic mycoplasmas. This information should be useful in understanding host tissue tropism and in developing diagnostic and vaccine strategies for these pathogenic mycoplasmas.
This research was Institute of Allergy
supported in part by Public Health and Infectious Diseases. We thank
Service Rose
grant Al 18540 from Garza for her secretarial
The National assistance.
References 1 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
15.
16. 17. 18.
19. 20.
Baseman JB, Banai M, Kahane I. Sialic acid residues mediate Mycoplasma pneumoniae attachment to human and sheep erythrocytes. Infect lmmun 1982; 38: 389-91. Baseman JB, Cole RM, Krause DC, Leith DK. Molecular basis for cytadsorption of Mycoplasma pneumoniae. J Bacterial 1982; 151: 1514-22. Biberfeld G, Biberfeld P. Ultrastructural features of Mycoplasma pneumoniae. J Bacterial 1970; 102: 855-61. Boatman ES. Morphology and ultrastructure of the mycoplasmatales. In: Barile MF, Razin S, eds. The mycoplasmas. Vol. 1: cell biology. New York: Academic Press 1979; 63-l 02. Collier AM, Baseman JB. Organ culture techniques with mycoplasmas. Ann NY Acad Sci 1973; 225: 277-89. Hu PC, Collier AM, Baseman JB. Surface parasitism by Mycoplasma pneumoniae of respiratory epithelium. J Exp Med; 145: 1328-43. Tully JG, Taylor-Robinson D, Cole RM, Rose DL. A newly discovered mycoplasma in the human urogenital tract. Lancet 1981; i: 1288-91. Wilson MH. Collier AM. Ultrastructural study of Mycoplasma pneumoniae in organ culture. J Bacterial 1976; 125: 332-9. Feldner J, Gobel U, Bredt W. Mycoplasma pneumoniae adhesin localized to tip structure by monoclonal antibody. Nature 1982; 298: 765-7. Hu PC, Cole RM, Huang YS et al. Mycoplasma pneumoniae infection: role of a surface protein in the attachment organelle. Science 1982; 219: 313-315. Dallo SF, Su CJ, Horton JR, Baseman JB. Identification of PI gene domain containing epitope(s) mediating Mycoplasma pneumoniae cytadherence. J Exp Med 1988; 167: 718-23. Krause DC, Baseman JB. Inhibition of Mycoplasma pneumoniae hemadsorption and adherence to respiratory epithelium by antibodies to a membrane protein. Infect lmmun 1983; 39: 1180-86. Clyde WA Jr, Hu PC. Antigenic determinants of the attachment protein of Mycoplasma pneumoniae shared by other pathogenic Mycoplasma species. Infect lmmun 1986; 51: 690-2. Morrison-Plummer J, Jones DH, Daly K, Tully JG, Taylor-Robinson D, Baseman JB. Molecular characterization of Mycoplasma genitalium species-specific and cross-reactive determinants: identification of an immunodominant protein of M. genitalium. lsr J Med Sci 1987; 23: 453457. Morrison-Plummer J, Lazzell A, Baseman JB. Shared epitopes between Mycoplasma pneumoniae major adhesin protein Pl and a 140 kilodalton protein of Mycoplasma genitalium. Infect lmmun 1987; 55: 49-56. Dallo SF, Horton JR, Su CJ, Baseman JB. Homologous regions shared by adhesrn genes of Mycoplasma pneumoniae and Mycoplasma genitalium. Microbial Pathogenesis 1989; 6: 69-73. Dallo SF, Chavoya A, Su CJ, Baseman JB. DNA and protein sequence homologies between the adhesins of Mycoplasma genitalium and Mycoplasma pneumoniae. Infect lmmun 1989; 57: 1059-65. lnamine JM, Loechel S, Collier AM, Barile MF, Hu PC. Nucleotide sequence of MgPa (mpg) operon of Mycoplasma genitalium and comparison to the Pl (mpp) operon of Mycoplasma pneumoniae. Gene 1989; 82: 259-67. Su CJ, Tryon VV, Baseman JB. Cloning and sequence analysis of cytadhesin PI gene from Mycoplasma pneumoniae. Infect lmmun 1987; 55: 3023-g. Baseman JB, Drouillard DL, Leith D, Tully JG. Absence of Mycoplasma pneumoniae cytadsorption
Mycoplasma
21 22. 23. 24.
cytadhesin
genes
375
protein PI in Mycoplasma genitalium and Mycoplasma gallisepticum. infect lmmun 1984; 43: 11035. Edward DG. A selective medium for pleuropneumonia-like organism. J. Gen Microbial 1947; 1: 23843. Tully JG, Rose DL, Whitcomb RF, Wenzel RP. Enhanced isolation of Mycoplasma pneumoniae from throat washings with a newly modified culture medium. J Infect Dis 1979; 139: 47882. Tully JG, Whitcomb RF, Clark HF. Williamson DL. Pathogenic mycoplasmas: cultivation and vertebrate pathogenicity of a new spiroplasma. Science 1971; 195: 892-894. Wood WI, Gitschier J, Lasky LA, Lawn RM. Base composition-independent hydridization in tetramethylammonium chloride: a method for oligonucleotide screening of hrghly complex gene libraries. Proc Nat1 Acad Sci USA 1985; 82: 1585-8.
