[Impact of the Interdisciplinary Chronic Pain Rehabilitation Programme in patients with and without sleep disorders]. / Impacto del Programa de Rehabilitación Interdisciplinario de Dolor Crónico en pacientes sin y con trastornos del sueño.

INTRODUCTION: Sleep disorders and chronic pain are linked to each other bidirectionally. Both are related to affective disorders, fatigue, depression, anxiety and drug abuse, and have a significant effect on quality of life. The Interdisciplinary Pain Programme (IDP) aims to relieve the patients' pain and improve their functionality by incorporating healthy postural, sleep and nutritional habits, relaxation techniques, physical exercise and cognitive-behavioural mechanisms. PATIENTS AND METHODS: A retrospective, observational, cross-sectional study was conducted. A total of 323 patients with chronic pain who completed the IDP were examined. They were assessed at the beginning and at the end of the programme with pain, depression, quality of life and insomnia scales, and were then compared between groups with and without insomnia, that is, with an insomnia severity index (ISI) less than 15 versus greater than or equal to 15. Fifty-eight patients were studied by means of polysomnography. RESULTS: A significant improvement (p < 0.0001) in pain, depression and quality of life, as assessed by the visual analogue scale (VAS), the Beck inventory and the Short Form-36 (SF-36) questionnaire was observed in chronic pain patients with an ISI below 15 and in those with an ISI greater than or equal to 15. The results were superior in the group of patients with insomnia. The presence of a high apnoea and hypopnoea index and periodic lower limb movements in patients was not related to improvements on the Beck, SF-36, ISI and VAS scales. CONCLUSIONS: In conclusion, IDP benefits patients with chronic non-cancer-induced pain in several affected areas, in addition to pain, due to a comprehensive treatment. Polysomnography can help diagnose specific pathologies and individualise pharmacological treatment.

TITLE: Impacto del Programa de Rehabilitación Interdisciplinario de Dolor Crónico en pacientes sin y con trastornos del sueño.Introducción. Los trastornos del sueño y el dolor crónico están relacionados bidireccionalmente. Ambos están relacionados con trastornos afectivos, fatiga, depresión, ansiedad y abuso de fármacos, y afectan significativamente a la calidad de vida. El objetivo del Programa Interdisciplinario de Dolor (PRID) es aliviar el dolor del paciente y mejorar su funcionalidad a través de la incorporación de hábitos posturales, del sueño y nutricionales saludables, técnicas de relajación, ejercicio físico y mecanismos cognitivoconductuales. Pacientes y métodos. Se realizó un estudio retrospectivo, observacional y transversal. Se examinó a 323 pacientes con dolor crónico que completaron el PRID. Se les evaluó al principio y al final del programa con escalas de dolor, depresión, calidad de vida e insomnio, y se les comparó entre grupos con y sin insomnio ­índice de gravedad del insomnio (ISI) menor de 15 frente a mayor o igual a 15­. Se estudió a 58 pacientes con polisomnografía. Resultados. Se observó una mejoría significativa (p < 0,0001) del dolor, la depresión y la calidad de vida evaluados mediante la escala analógica visual (EVA), el inventario de Beck y el cuestionario Short Form-36 (SF-36), tanto en pacientes con dolor crónico con ISI menor de 15 como ISI mayor o igual a 15. Los resultados fueron superiores en el grupo de pacientes con insomnio. La presencia de un índice de apneas e hipopneas elevado y movimientos periódicos de los miembros inferiores en los pacientes no se relacionó con la mejoría de las escalas de Beck, SF-36, ISI y EVA. Conclusiones. En conclusión, el PRID beneficia a los pacientes con dolor crónico no oncológico en varias esferas afectadas, además del dolor, mediante un tratamiento integral. La polisomnografía puede ayudar a diagnosticar patologías específicas e individualizar el tratamiento farmacológico.

International Cross-Sectional Survey among Healthcare Professionals on the Management of Cow's Milk Protein Allergy and Lactose Intolerance in Infants and Children.

Purpose: The present international survey among healthcare providers aimed to collect data on theoretical knowledge and clinical practices in the diagnosis and management of cow's milk protein allergy (CMPA) and lactose intolerance (LI) in infants. Methods: A global survey was conducted in several countries with diverse health care settings. The survey consisted of multiple-choice questions in 3 main domains: (1) understanding and clinical practices around CMPA and LI; (2) case scenarios; and (3) disease-specific knowledge and potential educational needs. Results: Responses were available from 1,663 participants. About 62% of respondents were general practitioners or general pediatricians, and the remainder were pediatric allergists/gastroenterologists (18%) or other health practitioners (20%). The survey identified knowledge gaps regarding the types of CMPA (IgE-mediated vs. non-IgE-mediated) and the clinical overlap with LI. The survey suggested diverse clinical practices regarding the use of hypoallergenic formulas, as well as misconceptions about the prebiotic benefits of lactose in extensively hydrolyzed formulas in non-breastfed infants with CMPA. Responses to the two case scenarios highlighted varying levels of awareness of the relevant clinical practice guidelines. While respondents generally felt confident in managing infants with CMPA and LI, about 80% expressed an interest for further training in this area. Conclusion: The current survey identified some knowledge gaps and regional differences in the management of infants with CMPA or LI. Local educational activities among general and pediatric healthcare providers may increase the awareness of clinical practice guidelines for the diagnosis and treatment of both conditions and help improve clinical outcomes.

El proceso vasculítico de las úlceras aftosas recidivantes orales podría ser inducido por una microbiota intestinal alterada. segunda parte / Vasculitis process of recurrent aphtae´s ulcers could be induced by altered gut microbiota. Second part

Basados en evidencia clínicas, epidemiológicas e inmunológicas, publicadas en los últimos años, consideramos que, cambios en la microbiota intestinal, pueden desempeñar un rol esencial en la incidencia de numerosos desordenes inflamatorios. Expertos reconocidos han encontrado que una microbiota comensal normal, puede, bajo ciertas circunstancias mutar a patogénica y provocar reacción inmunológica activa e inducir inflamación. En este trabajo se presenta la siguiente hipótesis: "la vasculitis como proceso fisiopatogénico de las RAU estaría inducida en su persistencia, morbilidad y recurrencia por una microbiota intestinal alterada."(AU)

We believe, based on clinical, epidemiological an immunological evidence that could be possible that changes in the intestinal microbiota may be an essential factoring in the incidence of oral inflammatory disorders. Experten have found that a normal microbiota ,, under certain circumstances, produce pathogenic mutations, inducing immunological reaction . This work presents the following hypothesis:: : " Vasculitis as the fisiopathogenic process of RAU coulbe induced in its persistencity, morbidity and recurrence by an altered gut microbiota. " (AU)

El procesovasculítico de las úlceras aftosas recidivantes orales podría ser inducido por una microbiota intestinal alterada. Primera p / Vasculitis process of recurrent aphtae´s ulcers could be induced by altered gut microbiota. First part

Los últimos estudios realizados por expertos en Genética, Biología y Microbiología tratan, entre otros capítulos, sobre la composición de la microbiota intestinal, sus propiedades benéficas y su funcionalidad. Además, especialmente resaltan la relación de esta microbiota con diferentes tejidos del organismo, estableciendo una interrelación con las microbiotas de los distintos órganos del cuerpo humano. En base a ello se establece en esta presentación una hipótesis, teniendo en cuenta la influencia que también podría ejercer la microbiota intestinal sobre la homeostasis y los problemas de inflamación y otras lesiones más severas de la mucosa bucal, por ejemplo, sobre las úlceras aftosas recidivantes (RAU).(AU)

Considering Recurrent Aphthae´s Ulcers, known as RAU, as local vasculitis lesions, with high morbidity, and difficult treatment, its etiology remains unknown until now. It was published about its high incidence and prevalence in HIV+ patients affecting immunocompetent individuals as well. It is referred an immune histochemical study of this illness that included a leucocitoclastic vasculitis It was analized immunology of oral mucosa and RAU microbiota.(AU)

Crystal structure of the central region of bovine fibrinogen (E5 fragment) at 1.4-A resolution.

The high-resolution crystal structure of the N-terminal central region of bovine fibrinogen (a 35-kDa E(5) fragment) reveals a remarkable dimeric design. The two halves of the molecule bond together at the center in an extensive molecular "handshake" by using both disulfide linkages and noncovalent contacts. On one face of the fragment, the Aalpha and Bbeta chains from the two monomers form a funnel-shaped domain with an unusual hydrophobic cavity; here, on each of the two outer sides there appears to be a binding site for thrombin. On the opposite face, the N-terminal gamma chains fold into a separate domain. Despite the chemical identity of the two halves of fibrinogen, an unusual pair of adjacent disulfide bonds locally constrain the two gamma chains to adopt different conformations. The striking asymmetry of this domain may promote the known supercoiling of the protofibrils in fibrin. This information on the detailed topology of the E(5) fragment permits the construction of a more detailed model than previously possible for the critical trimolecular junction of the protofibril in fibrin.

[The efficacy of neurophysiological examination in the diagnosis of carpal tunnel syndrome]. / Eficacia del examen neurofisiológico en el diagnóstico del síndrome del túnel del carpo.

INTRODUCTION: The validity of studies of nerve conduction in the diagnosis of carpal tunnel syndrome has been sufficiently demonstrated, especially the speed of nerve conduction across the carpus. It has also been proved that the result of the test varies according to its use. OBJECTIVE: This study is to evaluate the result of the study of nerve conduction in the diagnosis of carpal tunnel syndrome in a population attending a clinical neurophysiology department for examination of suspected neuro-muscular disorders of the upper limit. PATIENTS AND METHODS: We selected the cut-off points of the values of speed of nerve conduction along the median nerve from the thumb (E1) and palm of the hand (E2). Those showing the best sensitivity and specificity were chosen (53 and 51 m/s respectively). We assessed the pre-test and post-test probability to measure the examination result. There was little contribution from this examination to the diagnosis of carpal tunnel syndrome in this population. CONCLUSIONS: The high pre-test probability of a disorder is a cause of low efficacy of the examination done to confirm this and the opposite occurs when it is done to rule it out. The efficacy of an examination should be measured in the setting in which it is used since this does not depend only on its intrinsic characteristics but also on how it is used.

Diagnosis and documentation of central nervous system dysfunctions with craniocorpography after surgical removal of acoustic neurinomas.

Among other tests, craniocorpography (CCG) was performed in 21 patients after acoustic neurinoma surgery. After surgery, 17 patients (81%) had a developing vestibular compensation or an already normal CCG pattern; 3 patients (14%) had signs of persisting central nervous system dysfunction, either localized to the brain stem or in combination with a cerebellar dysfunction, and 1 patient showed a delayed but sufficient compensation after removal of a neurinoma that compressed central nervous system structures. Brain stem and cerebellar dysfunctions caused by tumor compression demonstrated a better vestibular compensation than dysfunctions caused by surgical manipulation, despite no evidence of cerebellar alteration. As an adjunct to complete neuro-otologic and neurologic examinations CCG could become a useful tool in the topodiagnosis of central nervous system dysfunctions after acoustic neurinoma surgery and therefore in the documentation and follow-up process of these patients.

Sodium transport kinetics, cell membrane lipid composition, neural conduction and metabolic control in type 1 diabetic patients. Changes after a low-dose n-3 fatty acid dietary intervention.

BACKGROUND: A decreased content of n-3 fatty acids in erythrocyte membrane of type 1 diabetic patients, which is inversely related to plasma levels of HbA(1c), has been reported previously. Our aim in this study was to observe the changes after a low-dose n-3 fatty acid (330 mg/day docosahexaenoic acid and 630 mg/day eicosapentanoic acid) dietary intervention in the lipid composition of cell membrane and metabolic control (measured according to plasma HbA(1c) levels). Since changes in both parameters may alter transmembrane sodium transport or influence parameters measuring target organ damage, we also studied the neural conduction quality and activity of four sodium transporters. METHODS: Eighteen type 1 diabetic patients were randomly assigned to continue their usual diet (control group) or to supplement their diet with a daily low dose of n-3 fatty acids (supplemented group). The changes between baseline and end values of the following parameters were compared: HbA(1c), lipid and phospholipid composition of cell membrane, activity of four ion carriers and neural conduction quality. RESULTS: The dietary supplementation caused statistically significant changes in membrane lipid composition, particularly an increase of C22:6 (n-3) and the total n-3 fatty acid (respectively +0.90+/-1.14% vs. -0.44+/-1.23% and +1.36+/-1.62% vs. -0.5+/-1.80%, p<0.05). After the dietary supplementation, we also observed a significant decrease of HbA(1c) (-2.00+/-1.9% vs. -0.13+/-0.48%, p<0.05), without significant changes in the dose of insulin required, an increase in the motor conduction velocity by the median nerve (+2.12 +/-1.35 m/s vs. -0.8+/-2.34 m/s, p<0.05) and a decrease of the V(max) of the Na(+)-Li(+) countertransport (-96.6+/-111.2 vs. +58.1+/-81.3 micromol/l cell/h(-1), p<0.01). CONCLUSION: A low-dose omega-3 fatty acid dietary supplementation may change the fatty acid composition of the cell membrane and improve the metabolic control of diabetes. Using this dose, we also observed a decrease of the maximal rate of Na(+)-Li(+) countertransport and a slight improvement of neural conduction.

Levansucrase from Acetobacter diazotrophicus SRT4 is secreted via periplasm by a signal-peptide-dependent pathway.

Acetobacter diazotrophicus SRT4 secretes a constitutive levansucrase (LsdA) (EC 2.4.1.10) that is responsible for sucrose utilization. Immunogold electron microscopical studies revealed that LsdA accumulates in the periplasm before secretion. The periplasmic and extracellular forms of the enzyme were purified to homogeneity. Both proteins exhibited similar physical and biochemical characteristics indicating that LsdA adopts its final conformation in the periplasm. The N-terminal sequence of mature LsdA was pGlu-Gly-Asn-Phe-Ser-Arg as determined by PSD-MALDI-TOFMS (post-source decay-matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry). Comparison of this sequence with the predicted precursor protein revealed the cleavage of a 30-residue typical signal peptide followed by the formation of the pyroglutamic acid (pGlu) residue. Thus, in contrast with other Gram-negative bacteria, A. diazotrophicus secretes levansucrase by a signal-peptide-dependent mechanism.

Structure and sites of phosphorylation of 14-3-3 protein: role in coordinating signal transduction pathways.

The 14-3-3 family are homo- and heterodimeric proteins whose biological role has been unclear for some time, although they are now gaining acceptance as a novel type of 'adaptor' protein that modulates interactions between components of signal transduction pathways, rather than by direct activation or inhibition. It is becoming apparent that phosphorylation of the binding partner and possibly also the 14-3-3 proteins may regulate these interactions. 14-3-3 isoforms interact with a novel phosphoserine (Sp) motif on many proteins, RSX1,2SpXP. The two isoforms that interact with Raf-1 are phosphorylated in vivo on Ser185 in a consensus sequence motif for proline-directed kinases. The crystal structure of 14-3-3 indicates that this phosphorylation could regulate interaction of 14-3-3 with its target proteins. We have now identified a number of additional phosphorylation sites on distinct mammalian and yeast isoforms.

Crystallization of a 14-3-3 protein.

Crystals of the tau (tau) isoform of the 14-3-3 family of proteins were grown and shown to belong to the orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 70.29, b = 79.3, c = 101.00 A. The crystals were needle-like in morphology and less than 10 micro m in two dimensions. Diffraction data were collected using synchrotron radiation sources from flash-cooled crystals. Native data extended to a resolution of 2.6 A and mercury and platinum derivatives diffracted to 3.4 and 3.9 A, respectively. The structure has been solved recently. Here the protein crystallization procedures, the characterization of the crystals and the correlation between crystal habit and diffraction quality are reported.

Post-translationally modified 14-3-3 isoforms and inhibition of protein kinase C.

This report compares the ability of individual members of the 14-3-3 protein family to inhibit particular protein kinase C (PKC) isoforms. We also show that two of these 14-3-3 isoforms (alpha and delta) specific to mammalian and avian brain are in vivo post-translationally modified forms of beta and zeta respectively. The presence of this modification enhances the activity of 14-3-3 as an inhibitor of protein kinase C nearly two fold. A method for analysing isoforms of 14-3-3 on acid-urea gels is also described. This permits the complete separation of all major isoforms and their unequivocal identification by a range of isoform specific antisera. The activity of recombinant 14-3-3 and isoforms renatured by a novel method after separation by reverse phase HPLC are compared. The effects of diacylglycerol and the phorbol ester, PMA (phorbol 1 2-myristate 13 acetate) on the inhibition suggest that one of the sites of interaction of 14-3-3 may be the cysteine-rich (C1) domain in PKC.

Single-step electrotransfer of reverse-stained proteins from sodium dodecyl sulfate-polyacrylamide gel onto reversed-phase minicartridge and subsequent desalting and elution with a conventional high-performance liquid chromatography gradient system for analysis.

Isolation of proteins from polyacrylamide electrophoresis gels by a novel combination of techniques is described. A given protein band from a reverse stained (imidazol-sodium dodecyl sulfate--zinc salts) gel can be directly electrotransferred onto a reversed-phase chromatographic support, packed in a self-made minicartridge (2 mm in thickness, 8 mm in internal diameter, made of inert polymeric materials). The minicartridge is then connected to a high-performance liquid chromatography system and the electrotransferred protein eluted by applying an acetonitrile gradient. Proteins elute in a small volume ( < 700 microL) of high-purity volatile solvents (water, trifluoroacetic acid, acetonitrile) and are free of contaminants (gel contaminants, salts, etc). Electrotransferred proteins were efficiently retained, e.g., up to 90% for radioiodinated alpha-lactalbumin, by the octadecyl matrix, and their recovery on elution from the minicartridge was in the range typical for this type of chromatographic support, e.g., 73% for alpha-lactalbumin. The technique was successfully applied to a variety of proteins in the molecular mass range 6-68 kDa, and with amounts between 50 and 2000 pmol. The good mechanical and chemical stability of the developed minicartridges, during electrotransfer and chromatography, allowed their repeated use. This new technique permitted a single-step separation of two proteins unresolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis due to their different elution from the reversed-phase support. The isolated proteins were amenable to analysis by N-terminal sequencing, enzymic digestion and mass spectrometry of their proteolytic fragments. Chromatographic elution of proteins from the reversed-phase mini-cartridge was apparently independent of the specific loading mode employed, i.e., loading by conventional loop injection or by electrotransfer.

14-3-3 alpha and delta are the phosphorylated forms of raf-activating 14-3-3 beta and zeta. In vivo stoichiometric phosphorylation in brain at a Ser-Pro-Glu-Lys MOTIF.

The 14-3-3 protein family has received considerable attention recently in the literature, because of the finding that beta and zeta isoforms interact with and activate Raf. We had previously shown that these 14-3-3 isoforms also exist as phosphorylated forms in mammalian and avian brain. The presence of this modification enhances the activity of 14-3-3 as an inhibitor of protein kinase C nearly 2-fold. In this report we show by a combination of electrospray mass spectrometry and protein microsequencing that alpha and delta are in vivo post-translationally modified forms of beta and zeta, respectively, and the site of phosphorylation, serine 185, is in a consensus sequence motif for proline-directed kinases.

Protein reverse staining: high-efficiency microanalysis of unmodified proteins detected on electrophoresis gels.

A methodology is presented for efficiently gaining structural information from electrophoresed proteins after on-gel detection by imidazole-sodium dodecyl sulfate-zinc reverse staining. As a consequence of reverse staining, (a) protein bands arise transparent against a deep white-stained background, limits of detection being in the femtomole range; (b) there is no loss of image when the gel is kept in distilled water (even during years); and (c) protein bands result immobilized, i.e., they do not diffuse upon gel storage. To recover reverse-stained proteins or fragments thereof from the gel, the immobilization of bands must first be abrogated by chelating the zinc ions from stain (protein mobilization). We had originally described mobilization at low pH by using citric acid. Here, we improve this procedure regarding the protein electrotransfer. We demonstrate that mobilization is efficiently done at neutral to alkaline pH by short-term (5 to 10 min) incubation of the gel in a buffer containing glycine or dithiothreitol prior to transfer. Moreover, mobilization was most simply performed by just adding the zinc chelating agent to the transfer buffer. Reverse staining and the new mobilization procedure made electrotransferring single protein bands from gel onto small-sized (13 x 5 mm2) PVDF membrane pieces in mini sandwich-like assemblies practical. Equipment is described for the protein electroblotting in such minisandwiches. Microsequence analysis of the electroblotted proteins showed initial yields in the range of those achieved when the transfer was done from unstained control gels. Protein bands kept in the reverse-stained gel for prolonged time periods (even for as long as 2 years) could be similarly analyzed.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression and structural analysis of 14-3-3 proteins.

The 14-3-3 family of proteins plays a role in a wide variety of cellular functions including regulation of protein kinase C and exocytosis. Using antisera specific for the N termini of 14-3-3 isoforms described previously and an additional antiserum specific for the C terminus of epsilon isoform, protease digestion of intact 14-3-3 showed that the N-terminal half of 14-3-3 (a 16 kDa fragment) was an intact, dimeric domain of the protein. Two isoforms of 14-3-3, tau and epsilon, were expressed in E. coli and their secondary structure was shown by circular dichroism to be identical to wild-type protein, and expression of N-terminally-deleted epsilon 14-3-3 protein showed that the N-terminal 26 amino acids are important for dimerization. Intact 14-3-3 is a potent inhibitor of protein kinase C, but the N-terminal domain does not inhibit PKC activity. Site-specific mutagenesis of several regions in the tau isoform of 14-3-3, including the mutation of a putative pseudosubstrate site to a potential substrate sequence, did not alter its inhibitory activity. Intact 14-3-3 proteins are phosphorylated by protein kinase C with a low stoichiometry, but truncated isoforms are phosphorylated much more efficiently by this kinase. This may imply that the proteins may adopt a different structural conformation, possibly upon binding to the membrane, which could modulate their activity. 14-3-3 proteins are found at high concentration on synaptic plasma membranes and this binding is mediated through the N-terminal 12 kDa of 14-3-3.

Mechanism of inhibition of protein kinase C by 14-3-3 isoforms. 14-3-3 isoforms do not have phospholipase A2 activity.

The ability of individual members of the 14-3-3 protein family to inhibit protein kinase C (PKC) has been studied by using a synthetic peptide based on the specific 80 kDa substrate for PKC (MARCKS protein) in two different assay systems. Recombinant 14-3-3 and isoforms renatured by a novel method after separation by reverse-phase h.p.l.c. were studied. The detailed effects of diacylglycerol and the phorbol ester phorbol 12-myristate 13-acetate on the inhibition were also investigated. This suggests that one of the sites of interaction of 14-3-3 may be the cysteine-rich (C1) domain in PKC. Since a region in secreted phospholipase A2 (PLA2) shares similarity with this domain, the ability of 14-3-3 to interact with mammalian PLA2 was studied. Cytosolic PLA2 has some similarity to the C2 region of PKC, and the effect of 14-3-3 on this class of PLA2 was also analysed. In contrast with a previous report, no PLA2 activity was found in brain 14-3-3, nor in any of the recombinant proteins tested. These include zeta 14-3-3 isoform, on which the original observation was made.

Multiepitope polypeptide of the HIV-1 envelope induces neutralizing monoclonal antibodies against V3 loop.

A gene encoding a multiepitope polypeptide (MEP) has been synthesized. It contains the information for (1) an 11-amino acid (aa) epitope from the C1 region of gp120 of HIV-1 and (2) 3 epitopes of 15 amino acids each, from the central part of the V3 loop of isolates MN, SC, and WMJII. These four segments are linked by the short spacer peptide AGGGA. This gene was cloned in a plasmid vector and expressed in Escherichia coli as a fusion product with a 62-aa fragment of human IL-2. The recombinant protein TAB1 was purified by washed pellet procedures and reversed-phase HPLC. TAB1 was recognized in ELISAs by 25 of 27 sera from seropositive individuals. Mice were immunized and several hybridomas were obtained. Two of them secrete monoclonal antibodies that react with synthetic peptides from isolates MN, WMJI, WMJIII, and SC with an affinity constant in the range of 10(8) M-1. They also recognized peptides from isolates SF2 and WMJII, but at much lower affinity. The results obtained from peptide ELISAs indicate that the putative epitope recognized by these MAbs lies within the sequence IHIGPGRAFYT. Classic neutralization assays demonstrated that MAb 2C4 neutralizes 50% of the MN isolate at 0.6 micrograms/ml but fails to neutralize IIIB and SF2 strains. The presence of antibodies directed against every one of the component peptides in the sera of rabbits immunized with TAB1 was also documented.

Crystallization and preliminary X-ray investigation of a recombinant outer membrane protein from Neisseria meningitidis.

A protein constituent of the outer membrane from Neisseria meningitidis (hereafter called P64K) has been crystallized using the hanging drop technique. Crystals are tetragonal with unit cell dimensions a = b = 136.84 A and c = 78.44 A, compatible with a single monomer of 64 kDa in the asymmetric unit. When exposed to high intensity synchrotron radiation, these crystals diffract X-rays to at least 2.9 A resolution, indicating that a high resolution structure analysis is feasible.