Polyamines and basic proteins stimulate activation by cAMP and catalytic activity of Mucor rouxii cAMP-dependent protein kinase

Partial activation of Mucor rouxii cAMP-dependent protein kinase by cAMP was obtained when kemptide was used as substrate, but complete activation was attained with cAMP plus protamine or histone. Full activation could not be achieved by increasing kemptide or cAMP concentration. Complete activation by cAMP could be obtained by addition of 10 microM polylysine, 10 microM lysine-rich histone or 0.5 mM spermine plus spermidine. The degree of stimulation could be up to 5-fold, depending on the amount of enzyme in the assay. The same concentrations of polycations increased 1.5-2.3-fold the Vmax of kemptide phosphorylation by the free catalytic subunits of both Mucor and bovine heart protein kinases; 10 microM polyarginine inhibited completely the activity of both enzymes.

[Complicated torsion of the gallbladder. Presentation of a clinical case]

A case of gallbladder torsion complicated by sigmoid volvulus and sub-torsion of the ileus is reported because of the difficulty of diagnosis, conditioned by polymorphic symptomatology, the expression of a variety of causes and contributing causes that play an important role in the greater or less onset of dramatic symptomatology, and because of the rarity of the pathology.

Mammalian growth-associated H1 histone kinase: a homolog of cdc2+/CDC28 protein kinases controlling mitotic entry in yeast and frog cells

Mammalian growth-associated H1 histone kinase, an enzyme whose activity is sharply elevated at mitosis, is similar to cdc2+ protein kinase from Schizosaccharomyces pombe and CDC28 protein kinase from Saccharomyces cerevisiae with respect to immunoreactivity, molecular size, and specificity for phosphorylation sites in H1 histone. Phosphorylation of specific growth-associated sites in H1 histone is catalyzed by yeast cdc2+/CDC28 kinase, as shown by the in vitro thermal lability of this activity in extracts prepared from temperature-sensitive mutants. In addition, highly purified Xenopus maturation-promoting factor catalyzes phosphorylation of the same sites in H1 as do the mammalian and yeast kinases. The data indicate that growth-associated H1 kinase is encoded by a mammalian homolog of cdc2+/CDC28 protein kinase, which controls entry into mitosis in yeast and frog cells. Since H1 histone is known to be an in vivo substrate of the mammalian kinase, this suggests that phosphorylation of H1 histone or an H1 histone counterpart is an important component of the mechanism for entry of cells into mitosis.

Cytogenetic follow-up from direct preparation to advanced in vitro passages of a human malignant glioma

In order to evaluate which cytogenetic evolutionary patterns take place during the in vitro establishment of a permanent glioma cell line, cytogenetic follow-up was performed on direct preparations and primary cultures from a malignant astrocytoma and on serial passages for more than 2 years of in vitro propagation. Sixteen passages were studied, and the presence of a marker chromosome in direct preparations and after in vitro growth permitted us to identify the clonal evolution of the resulting permanent cell line. Near-triploid cells present in the direct study became the main cell population in vitro; chromosomal losses and the acquisition of a few new marker chromosomes were also characteristic features, leading to a stable modal number of around 60 chromosomes in the last passages analyzed. The results provide new evidence of the existence of more than one pattern of chromosomal evolution during the in vitro establishment of human gliomas.

Regulation of p34cdc2 protein kinase during mitosis

The cell-cycle timing of mitosis in fission yeast is determined by the cdc25+ gene product activating the p34cdc2 protein kinase leading to mitotic initiation. Protein kinase activity remains high in metaphase and then declines during anaphase. Activation of the protein kinase also requires the cyclin homolog p56cdc13, which also functions post activation at a later stage of mitosis. The continuing function of p56cdc13 during mitosis is consistent with its high level until the metaphase/anaphase transition. At anaphase the p56cdc13 level falls dramatically just before the decline in p34cdc2 protein kinase activity. The behavior of p56cdc13 is similar to that observed for cyclins in oocytes. p13suc1 interacts closely with p34cdc2; it is required during the process of mitosis and may play a role in the inactivation of the p34cdc2 protein kinase. Therefore, the cdc25+, cdc13+, and suc1+ gene products are important for regulating p34cdc2 protein kinase activity during entry into, progress through, and exit from mitosis.

Visceral leishmaniasis in patients infected with human immunodeficiency virus (HIV)

In an 8-month period nine patients with human immunodeficiency virus (HIV) infection were diagnosed as having visceral leishmaniasis; all diagnoses were based on cultures (eight from bone marrow and one from the skin). Visceral leishmaniasis developed before full-blown acquired immunodeficiency syndrome (AIDS) in seven patients and at the same time as or after AIDS in the other two patients. Three patients had a history of leishmaniasis. Clinical manifestations and laboratory findings were atypical. Leishmania species were cultured from samples taken from all patients; however, six patients had an insignificant antileishmanial antibody titer and Leishmania amastigotes were not seen in their bone marrow smears. Four isolates were identified by isoenzyme analysis as Leishmania donovani infantum. Five patients died, including two patients who had completed at least one 3-week course of therapy with N-methylglucamine antimoniate. Screening should be done for visceral leishmaniasis in patients with HIV infection who live or travel in areas where the disease is endemic. The diagnosis of visceral leishmaniasis may frequently be missed if cultures are not done.

Visceral leishmaniasis (kala-azar) as an opportunistic infection in patients infected with the human immunodeficiency virus in Spain

In an area endemic for visceral leishmaniasis, 16 patients with human immunodeficiency virus (HIV) infection developed the disease. All belonged to populations at risk for AIDS (15 were intravenous drug abusers). Five patients fulfilled the criteria for full-blown AIDS, and two more fulfilled them after diagnosis of leishmaniasis. All presented with the classic manifestations of visceral leishmaniasis, but leishmania serology was negative in 15 patients (93%). Leishmania donovani amastigotes were identified in the bone marrow in all cases. Most patients responded initially to treatment with pentavalent antimonial drugs, but seven (43%) followed a chronic course, with multiple relapses in five, despite alternative treatments. Visceral leishmaniasis occurred in patients with different levels of depression of the CD4 to CD8 lymphocyte ratio. Mortality was 37% (six patients) and was independent of the chronic-relapsing course of the disease. In no case was leishmaniasis the primary cause of death. Our data establish that visceral leishmaniasis is an opportunistic infection in HIV-infected patients, and we suggest that in endemic areas it should be considered an indicator disease for the diagnosis of AIDS.

[Pneumonia caused by Mycoplasma pneumoniae]

Mycoplasma pneumoniae is a common causative agent of community acquired pneumonia. To assess its epidemiological, clinical and evolutive features in our area, we retrospectively analyzed 88 instances which occurred during 10 years. Both sexes were similarly involved, with a higher incidence in younger patients (mean age: 22 years). A clear seasonal predominance was not detected during the study period. In nearly one half of instance there were similar respiratory episodes in the same household. Cough was a constant symptom, followed by fever and headache. The absence of leukocytosis and the presence of cryoagglutinins were suggestive data. Pulmonary infiltration in the chest radiogram was unilateral in most cases, with a segmental distribution and predominating in the lower lobes. Hilar lymph nodes, pleural effusion and cavitation were present in a limited number of instances. All patients were cured without sequelae. The occurrence of particular epidemiological, clinical and laboratory data may be very helpful in suggesting the diagnosis of pneumonia due to Mycoplasma pneumoniae.

[Pneumococcal endocarditis: apropos of 3 cases]

Streptococcus pneumoniae is a common pathogen in man. The incidence of endocarditis caused by this organism has diminished in the last decades, and now it is an exceptional condition. Three patients with pneumococcal endocarditis are reported. Their clinical and epidemiological features are reviewed and compared with previous literature. One of the instances was due to a strain with high resistance to penicillin; vancomycin was a valid alternative therapy.

Conservation of mitotic controls in fission and budding yeasts

In fission yeast, the initiation of mitosis is regulated by a control network that integrates the opposing activities of mitotic inducers and inhibitors. To evaluate whether this control system is likely to be conserved among eukaryotes, we have investigated whether a similar mitotic control operates in the distantly related budding yeast S. cerevisiae. We have found that the protein kinase encoded by the mitotic inhibitor gene wee1+ of fission yeast, which acts to delay mitosis, is able also to delay the initiation of mitosis when expressed in S. cerevisiae. The wee1+ activity is counteracted in S. cerevisiae by the gene product of MIH1, a newly identified gene capable of encoding a protein of MW 54,000, which is a structural and functional homolog of the cdc25+ mitotic inducer of fission yeast. Expression of wee1+ in a mih1- strain prevents the initiation of mitosis. These data indicate that important features of the cdc25+-wee1+ mitotic control network identified in S. pombe are conserved in S. cerevisiae, and therefore are also likely to be generally conserved among eukaryotic organisms.

Clinical presentation of Bacillus Calmette-Guérin infections in patients with immunodeficiency syndromes

Nine children with immunodeficiency syndromes who developed persistent or disseminated Bacillus Calmette-Guérin (BCG) infections after BCG vaccination at birth were observed in Santiago, Chile, over a period of 10 years. This represents a risk for persistent or disseminated BCG infections of 3.4/1,000,000 vaccinated newborns. This may closely reflect the incidence of severe combined immunodeficiency syndromes, cellular immunodeficiency syndromes and chronic granulomatous disease in the study area. The clinical presentation and course of the infection varied considerably depending on the underlying immunodeficiency syndrome. Two patients with severe combined immunodeficiency presented with cutaneous nodules in the absence of any local reaction at the site of BCG vaccination. Both patients died of disseminated BCG infection within the first year of life. Four patients with cellular immunodeficiency syndromes presented with regional lymphadenitis resistant to treatment after the fifth month of life. Three of these patients had specific unresponsiveness to tuberculin and survived from 5 to 6 years of age. Two boys with X-linked chronic granulomatous disease presented with regional lymphadenitis in the first 3 months of life. A girl with autosomal recessive chronic granulomatous disease presented at 18 months of age with regional lymphadenitis. All three patients with chronic granulomatous disease had positive tuberculin reactions and died from infections other than BCG.

[Proposal for anatomo-functional instrumental control of dysfunctional bilio-digestive Roux-en-Y anastomosis]

Various techniques are used for the anatomo-functional study of bilio-digestive anastomoses on jejunal loop autonomized according to Roux. Here a transparietojejunal endoscopic investigation is proposed that permits direct sight of the anastomosis, biliary sampling for cultural examination and dilatative type therapeutic manoeuvres, biopsies or extractions of residual stones from the bile ways that would not otherwise be possible without further surgery. A clinical case is reported.

Lemierre's disease: postanginal bacteremia and pulmonary involvement caused by Fusobacterium necrophorum

The combination of acute pharyngotonsillitis, neck pain, fever, and pulmonary septic emboli caused by Fusobacterium necrophorum in a healthy young person is extremely rare. The entity was described by Lemierre in 1936 as a typical syndrome easy to recognize and diagnose exclusively on clinical grounds. A case of Lemierre's disease is reported, and 10 other cases found in the medical literature are reviewed.

Two different intrachain cAMP sites in the cAMP-dependent protein kinase of the dimorphic fungus Mucor rouxii

cAMP sites of the cAMP-dependent protein kinase from the fungus Mucor rouxii have been characterized through the study of the effects of cAMP and of cAMP analogs on the phosphotransferase activity and through binding kinetics. The tetrameric holoenzyme, which contains two regulatory (R) and two catalytic (C) subunits, exhibited positive cooperativity in activation by cAMP, suggesting multiple cAMP-binding sites. Several other results indicated that the Mucor kinase contained two different cooperative cAMP-binding sites on each R subunit, with properties similar to those of the mammalian cAMP-dependent protein kinase. Under optimum binding conditions, the [3H]cAMP dissociation behavior indicated equal amounts of two components which had dissociation rate constants of 0.09 min-1 (site 1) and 0.90 min-1 (site 2) at 30 degrees C. Two cAMP-binding sites could also be distinguished by C-8 cAMP analogs (site-1-selective) and C-6 cAMP analogs (site-2-selective); combinations of site-1- and site-2-selective analogs were synergistic in protein kinase activation. The two different cooperative binding sites were probably located on the same R subunit, since the proteolytically derived dimeric form of the enzyme, which contained one R and one C component, retained the salient properties of the untreated tetrameric enzyme. Unlike any of the mammalian cyclic-nucleotide-dependent isozymes described thus far, the Mucor kinase was much more potently activated by C-6 cAMP analogs than by C-8 cAMP analogs. In the ternary complex formed by the native Mucor tetramer and cAMP, only the two sites 1 contained bound cAMP, a feature which has also not yet been demonstrated for the mammalian cAMP-dependent protein kinase.

Regulation of the cell cycle timing of mitosis

Considerable advances have been made recently in our understanding of how the cell cycle timing of mitosis is regulated. This has come about because links have been established between two independent areas of research, one based on a genetic approach using the fission yeast Schizosaccharomyces pombe and the second based on a biochemical approach using Xenopus and starfish oocytes. In this chapter we review work that has identified a number of the mitotic regulating genes in fission yeast and has established links with controls operative in multicellular eukaryotes.

Chromosomal involvement secondary to -22 in human meningiomas

Cytogenetic analyses have been performed on cultures in vitro from 32 human meningiomas, seeking chromosomal anomalies in addition to characteristic monosomy 22. Eight cases showed stem lines with normal karyotype, whereas, monosomy 22 as the only chromosomal deviation characterized the stem line of ten tumors. In 14 samples stem lines or modal numbers displaying numerical deviations (other than -22) and/or structural rearrangements were found. A hyperdiploid modal number was present in three, whereas, it was hypodiploid in the remainder. Numerical deviations in these tumors involved mainly #14 by losses, and also #22; recurrent structural rearrangements involving 1p and 11p were also characteristic features. Thus, these results could imply that involvement of #14, 1p, and 11p would be a form of clonal evolution secondary to monosomy 22 in certain meningiomas.

Synthesis of Saccharomyces cerevisiae invertase by Schizosaccharomyces pombe

In order to gain information on the ability of the glycosylation system of Schizosaccharomyces pombe to process heterologous glycoproteins, the expression of Saccharomyces cerevisiae invertase in the former yeast was studied. Sc. pombe cells are able to produce enzymatically active invertase from the S. cerevisiae SUC2 gene introduced by transformation and the enzyme is glycosylated and secreted into the cell wall. However, Sc. pombe transformants do not glycosylate the heterologous enzyme as their own invertase since it is not bound by the lectin from Bandeiraea simplicifolia seeds, which indicates the absence of terminal galactose residues. Moreover, the electrophoretic mobility of the heterologous invertase is similar to that of the large enzyme from S. cerevisiae, both in its native form and after being deglycosylated with Endo H. These results suggest that the polypeptide chain of S. cerevisiae invertase is the primary factor for the glycosylation in Sc. pombe cells.

Expression of the SV40 promoter in fission yeast: identification and characterization of an AP-1-like factor

The SV40 promoter is expressed well in the fission yeast S. pombe, and it initiates transcription at the same site as in mammalian cells. The majority of the enhancer sequences, however, do not contribute to this activity. DNAase I footprint analysis of the promoter revealed the presence of an AP-1-like factor in S. pombe cells that protects a region of the promoter almost identical to that protected by human AP-1. The specificity of binding of the yeast and mammalian AP-1 proteins was found to be similar. We have found two AP-1-like binding activities in budding yeast cells, one of which appears quite distinct from the binding activity of the product of the budding yeast GCN4 gene. We also demonstrate that in fission yeast the AP-1 binding site can act as an upstream activating sequence. The DNA-protein complexes containing the mammalian AP-1 and fission yeast AP-1-like factors are sensitive to phosphatase treatment, indicating that they may be phosphorylated.

Chromosomal composition of a series of 22 human low-grade gliomas

G-banded chromosomal analysis was performed on direct and/or in vitro cultures of 22 low-grade gliomas, including nine grade I-II astrocytomas, nine oligodendrogliomas, one mixed tumor oligodendroglioma-astrocytoma, and three ependymomas. Normal diploid stem lines were present in most astrocytomas and oligodendrogliomas, whereas, all three ependymomas displayed polyploid modal numbers. However, secondary cell lines showed the presence of clonal recurrent numerical abnormalities, mainly polysomy 7, monosomy 10 and 22, and loss of the Y chromosome. Clonal structural rearrangements were present with a low incidence; they mainly involved chromosomes #1 and #7. These patterns of chromosome involvement seem to correlate with the scarce previous cytogenetic banding data available from low-grade gliomas. They are also similar to the chromosome alterations found in high-grade gliomas.

Purulent meningitis after percutaneous radiofrequency trigeminal rhizotomy

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Deletion 3p in two lung adenocarcinomas metastatic to the brain

Cytogenetic analysis by direct and in vitro preparation of brain metastatic lesions from two lung adenocarcinomas have shown the presence of a recurrent chromosomal abnormality, del(3p). These results add new evidence about the presence of 3p- marker chromosomes in adenocarcinoma of the lung.

Alpha-glucan synthesis on a protein primer. A reconstituted system for the formation of protein-bound alpha-glucan

Reconstitution experiments with the DEAE-cellulose-treated enzymes, engaged in a two-step mechanism of synthesis of alpha-glucan bound to protein, are performed. Urea/sodium dodecyl sulfate/polyacrylamide gel electrophoretic analysis of the radioactive products synthesized by the reconstituted system shows highly glucosylated, labeled bands, whose apparent molecular masses change with the acrylamide concentration in the gels. The long carbohydrate chains synthesized during the second step arise from the sequential addition of glucosyl moieties to the glucoprotein formed during the first step. A deglucosylation experiment confirms that the product of the reconstituted system originates from the 38-kDa glucosylated component of the reaction 1 product by the addition of beta-amylase-sensitive glucosyl moieties. Our data suggest that specific phosphorylases and starch synthetases are found in potato tuber, which are capable of utilizing reaction 1 product as primer for the synthesis of protein-bound glucan.

Fournier's syndrome of urogenital and anorectal origin. A retrospective, comparative study

Twenty-eight patients with genital and perianal necrotizing infections are described. The patients were divided into three groups according to the primary site of infection: group 1, anorectal (14 patients); group 2, urologic (ten patients), and group 3, idiopathic (four patients). The overall mortality was 25 percent, 28.5 percent for the anorectal group and 10 percent for the urologic group, although this difference is not statistically significant. Necrotizing infections of anorectal origin were more severe and had a less typical way of presentation, with subsequent delay in diagnosis and a higher rate of myonecrosis. As a consequence, more debridements and more fecal derivations had to be performed. The etiologic agents were the same among the three groups and comprised a number of anaerobes (Bacteroides spp, gram-positive cocci) as well as aerobes (microorganisms belonging to the Enterobacteriaceae and S. faecalis). Necrotizing fasciitis was the pathologic picture of nine of ten patients with Fournier's gangrene of urogenital origin and seven of 14 with an anorectal source. Synergistic necrotizing cellulitis was identified in half of those secondary to anorectal origin and only one of those with a urologic source.

alpha-Glucan synthesis on a protein primer, uridine diphosphoglucose: protein transglucosylase I. Separation from starch synthetase and phosphorylase and a study of its properties

It was found that the DEAE-cellulose-treated UDP-Glc:protein transglucosylase I catalyzing the first step (reaction 1) in the formation of alpha-glucan bound to protein in potato tuber is not only specific for the glucosyl donor but also for the endogenous acceptor. A single radioactive 38-kDa macromolecular component appeared during denaturing polyacrylamide gel electrophoresis of reaction 1 product. The labeled component is probably the polypeptide subunit of the endogenous acceptor which is being glucosylated. The radioactivity incorporated in reaction 1 product was isolated from a protease digest as a low-molecular-mass glucopeptide fraction. A beta-elimination reaction carried out in the presence of a reducing agent demonstrated that only one glucosyl moiety is transferred from UDP-Glc to the aminoacyl residue, thus forming an O-glucosidic linkage. 3H-labeled sodium borohydride showed that serine and threonine are involved in the peptide bond to glucose. Ion-exchange chromatography on DEAE-cellulose, affinity chromatography on concanavalin-A--Sepharose, gel filtration on Sephacryl S-300 and sucrose density gradient centrifugation failed to separate the enzyme catalyzing reaction 1 from the endogenous acceptor.

Polymeric structure of the cyclic AMP-dependent protein kinase from the dimorphic fungus Mucor rouxii and purification of its catalytic subunit

The polymeric structure of the cyclic AMP-dependent protein kinase (E.C.2.7.1.37) from the dimorphic fungus Mucor rouxii was analyzed through studies of gel filtration and sucrose gradient centrifugation of the holoenzyme and its subunits and by photoaffinity labeling of the regulatory subunit. It was demonstrated that it is a tetramer composed by two regulatory subunits (R) of mol. wt. 75 000 and two catalytic subunits (C) of mol. wt. 41 000 forming a holoenzyme R2C2 of mol. wt. 242 000. Frictional coefficients of 1.55 and 1.62 for the holoenzyme and for the regulatory dimer, respectively, indicate a significant degree of dimensional asymmetry in both molecules. A procedure for the purification of the catalytic subunit of the kinase is presented. The holoenzyme could be bound to a cyclic AMP-agarose column and the catalytic subunit could be eluted by 0.5 M NaCl, well resolved from the bulk of protein. This particular behaviour of the holoenzyme in cyclic AMP-agarose chromatography allowed the inclusion of this step in the purification of the catalytic subunit and corroborated that the holoenzyme was not dissociated by cyclic AMP alone. The isolated catalytic subunit displays Michaelis-Menten behavior towards kemptide, protamine and histone and is inhibited by sulfhydryl reagents, indicating that the molecule has at least one cysteine residue essential for enzyme activity. The catalytic activity of the isolated C subunit is inactivated by the mammalian protein kinase inhibitor, and is inhibited by the regulatory subunit from homologous and heterologous sources. In general, the properties of the catalytic subunit suggest a structural similarity between Mucor and mammalian C subunits.

Subcellular localization and glycoprotein nature of the invertase from the fission yeast Schizosaccharomyces pombe

The subcellular localization of the enzyme invertase in Schizosaccharomyces pombe cells, both repressed and derepressed for synthesis of the enzyme, was studied. Most of the invertase was found to be located outside the plasma membrane and only a small percentage was found to be associated to membranes. A substantial portion of the external enzyme remained firmly bound to cell-wall material. All of the invertase recovered in soluble form from cellular extracts reacted with concanavalin A and with the lectin from Bandeiraea simplicifolia seeds, indicating the presence in the enzyme of a carbohydrate moiety which probably contains terminal mannosyl (or structurally related) and galactosyl residues. The possibility of the presence of two different forms of invertase in S. pombe was considered. An intracellular, soluble form of invertase, devoid of carbohydrate, similar to the small invertase of the budding yeast Saccharomyces cerevisiae, was not found in S. pombe. However, the Michaelis constant for sucrose of the enzyme present in repressed cells was smaller than that of the invertase synthesized under derepressing conditions, although this difference could also be the result of a different pattern of glycosylation of the invertase synthesized under different growth conditions.

Regulation of cyclic AMP phosphodiesterase from Mucor rouxii by phosphorylation and proteolysis. Interrelationship of the activatable and insensitive forms of the enzyme

DEAE-cellulose chromatography of mycelial extracts of Mucor rouxii grown to mid-exponential phase resolves two types of low-Km cyclic AMP phosphodiesterase (EC 3.1.4.17; PDE): PDE I, highly activatable (4-6-fold) by phosphorylation or proteolysis, and PDE II, unresponsive to activation. The enzymic profile of PDE activity obtained from germlings shows only PDE I activity, whereas PDE activity from mycelia grown to stationary phase is eluted from the DEAE-cellulose column at the position of PDE II, and like PDE II is unresponsive to activation. Endogenous proteolysis or controlled trypsin treatment transforms PDE I into PDE II. The insensitive forms of PDE exhibit a slightly smaller sedimentation coefficient than the activatable forms, as judged by sucrose-gradient centrifugation. The basal activity of the highly activatable form of PDE is elevated almost to the value in the presence of trypsin on storage at 4 degrees C in the absence of proteinase inhibitors. Benzamidine, leupeptin, antipain or EGTA prevents the activation produced by storage. PDE I remains strongly activatable by phosphorylation and proteolysis after resolution by polyacrylamide-gel electrophoresis.

Protein kinase from Mucor rouxii. Unshielding of new cyclic AMP binding sites upon dissociation of the ternary complex holoenzyme-cyclic AMP

Cyclic AMP binding to Mucor rouxii protein kinase holoenzyme and free regulatory subunit was measured by the classical membrane filtration technique and by equilibrium dialysis. The results obtained demonstrate that the filtration method can be used without loss of any cyclic AMP binding site. Both methods unambiguously demonstrate that the number of molecules of cyclic AMP bound to the holoenzyme are half of those bound to the regulatory subunit. This result suggests that unshielding of new cyclic AMP binding sites occurs upon dissociation of the ternary complex holoenzyme-cyclic AMP.