This paper describes the sequence of adenylate kinase (Mg-ATP + AMP * Mg-ADP + ADP) from maize chloroplasts. This light-inducible enzyme is important for efficient CO, fixation in the C, cycle, by removing and recycling AMP produced in the reversible pyruvate phosphate dikinase reaction.The complete sequence was determined by analyzing peptides from cleavages with trypsin, Asp-N protease and CNBr and subcleavage of a major CNBr peptide with chymotrypsin. N-terminal Edman degradation and carboxypeptidase digestion established the terminal residues. Electrospray mass spectrometry confirmed the final sequence of 222 residues (Mr = 24867) including one cysteine and one tryptophan.The sequence shows this enzyme to be a long-variant-type adenylate kinase, the nearest relatives being adenylate kinases from Enterobacteriaceae. Alignment of the sequence with the adenylate kinase from Escherichiu coli reveals 44% identical residues. Since the E. coli structure has been published recently at 0.19-nm resolution with the inhibitor adenosine(5')pentaphospho(5')adenosine Mol. Biol. 224, 159-1771, catalytically essential residues could be compared and were found to be mostly conserved. Surprisingly, in the nucleotidebinding Gly-rich loop Gly-Xaa-Pro-Gly-Xaa-Gly-Lys the middle Gly is replaced by Ala. This is, however, compensated by an Ile+Val exchange in the nearest spatial neighborhood. A Thr-Ala exchange explains the unusual tolerance of the enzyme for pyrimidine nucleotides in the acceptor site.Adenylate kinases are small monomeric enzymes (21 -27 kDa) which catalyze the reversible transfer of a phosphoryl group from ATP to AMP according to the reaction:Mg-ATP + AMP * Mg-ADP + ADP [l]. Thereby, they perform the recycling of AMP produced in biosynthetic processes and enhance the energy charge signal in the cell. Although the sequences of some 30 adenylate kinases are known, as well as five well-resolved X-ray structures with different substrates in different conformations [2], so far we have little structural information on the enzymes from plants. Only recently two very similar cDNA sequences from rice were cloned, both showing the highest similarity to mammalian mitochondria1 AK2 [3].C, plants, like maize, have a particularly efficient CO, fixation by the C, cycle at the expense of ATP to AMP conversion in the pyruvate phosphate dikinase reaction. Because of the reversibility of the latter reaction, these plants need an efficient AMP recycling ; not surprisingly, an approximately 50-fold higher adenylate kinase (AK) content than in C, plants was found [4, 51. Genetic studies have shown that maize has only one AK gene, localized on chromosome 6Correspondence to E. Schiltz, Institut fur Organische Chemie und Biochemie, Albertstrasse 21, D-79104 Freiburg, GermanyAbbreviations. AK, adenylate kinase ; Ap5A, adenosine(5')pentaphospho(5')adenosine. Note. The sequence data will appear in the PIR Sequence Database under accession number S43039.[6] and that more than 90% of the light-inducible enzyme is found in mesophyll chloroplast...

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PURPOSE: Advances in treatment have increased survival rates and quality of life of pediatric CNS tumor patients leading to a growing number of long-term survivors. However, there is sufficient clinical and scientific evidence for the need of a highly specialized lifelong follow-up care due to multidimensional late effects. Furthermore, adolescence and young adulthood are challenging age periods when patients frequently get lost to follow-up potentially having severe impact on health and well-being. Since 2020, we have established a structured transfer of long-term survivors older than 18 years to a newly founded highly specialized adult care follow-up setting for childhood cancer survivors (IONA). The aim of this study was to evaluate the current transition process. RESEARCH DESIGN: The standard of care transition process at the neuro-oncology unit of the MUV includes a joint appointment with the patient, a pediatric neuro-oncologist, psychologist and/or social worker and the team of the adult care facility (physician, psychologist). Different elements are used to end care safely in the pediatric structure and building trust in the upcoming out-patient-department at the same time. The transition process was evaluated statistically and analyzed qualitatively with regard to the factors that define a safe transition. RESULTS: After two years (01/2020-12/2021) 114 patients had a joint transition appointment, two patients contacted IONA directly. Shortly after the joint appointment all patients had a scheduled follow-up meeting at IONA. 102 patients (87.9%) showed up, seven patients (6%) already had a planned appointment, two patients (1.7%) were in contact with IONA but had no possibility to show up in person. Only five patients (4.3%) did not attend the appointment and were lost to follow-up. CONCLUSION: A structured interdisciplinary transition concept is a successful option to establish controlled and patient-safe transition from pediatric to adult care setting.

Paraneoplastic neurological syndromes describe a very heterogeneous group of neurological disorders. Paraneoplastic cerebellar degeneration is frequently associated with gynecological tumors, lung cancer and Hodgkin lymphoma. The following case report shows the typical course of this disease as well as the diagnostic and therapeutic challenges. Furthermore the importance of interdisciplinary cooperation between neurology, oncology and palliative care for prognosis and symptom stabilization is highlighted.