The gene encoding ,-amylase was cloned from Bacillus polymyxa 72 into Escherichia coli HB101 by inserting HindIll-generated DNA fragments into the Hindm site of pBR322. The 4.8-kilobase insert was shown to direct the synthesis of ,-amylase. A 1.8-kilobase AccI-AccI fragment of the donor strain DNA was sufficient for the I8-amylase synthesis. Homologous DNA was foun4 by Southern blot analysis to be present only in B. polymyxa 72 and not in other bacteria such as E. coli or B. subtilis. B. polymyxa, as well as E. coli harboring the cloned DNA, was found to produce enzymatically active fragments of (-amylases (70,000, 56,000, or
A previous paper described the complete amino acid sequences of sarcotoxins IA, IB and IC, which are a group of potent antibacterial proteins with almost identical primary structures produced by Sarcophaga peregrina (fleshfly) larvae [Okada & Natori (1985) J. Biol. Chem. 260, 7174-7177]. The present paper describes the cDNA cloning and complete nucleotide sequencing of a cDNA clone for sarcotoxin IA. The C-terminal amino acid residue of sarcotoxin IA deduced from the nucleotide sequence was glycine, whereas it was found to be arginine by amino acid sequencing of purified sarcotoxin IA. Analysis of the elution profiles on h.p.l.c. of the synthetic derivatives of sarcotoxin IA showed that the C-terminal amino acid residue of authentic sarcotoxin IA is amidated arginine, which is probably produced by enzymic cleavage of terminal glycine.
We have isolated two temperature-sensitive Saccharomyces cerevisiae mutants which exhibit a deficiency in mannose outer chain elongation of asparagine-linked oligosaccharide. The size of yeast glycoprotein, secretory form of invertase, of one mutant (och1) was slightly larger than that of the sec18 mutant at the non-permissive temperature, while that of the other mutant (och2) was almost the same as that of the sec18 mutant. Unlike sec mutants, the och mutants were not deficient in secretion of invertase. The och1 mutant showed a 2+:2- cosegregation with regard to the temperature sensitivity and mannose outer chain deficiency, suggesting that a single gene designated as OCH1 is responsible for these two phenotypes. The och1 mutant stopped its growth at the early stage of bud formation and rapidly lost its viability at the non-permissive temperature. The och1 mutation was mapped near the ole1 on the left arm of chromosome VII. The och1 mutant cells accumulated the external invertase containing a large amount of core-like oligosaccharides (Man9-10GlcNAc2) and a small amount of high mannose oligosaccharides (greater than Man50GlcNAc2) at the non-permissive temperature. Production of the active form of human tissue-type plasminogen activator was increased in the och1 mutant compared with the parental strain, suggesting the potential advantage of this mutant for the production of mammalian-type glycoproteins which lack mannose outer chains in yeast.
Danon disease, primary lysosome-associated membrane protein-2 (LAMP-2) deficiency, is characterized clinically by cardiomyopathy, myopathy and intellectual disability in boys. Because Danon disease is inherited in an X-linked dominant fashion, males are more severely affected than females, who usually have only cardiomyopathy without myopathy or intellectual disability; moreover, the onset of symptoms in females is usually in adulthood. We describe a girl with Danon disease who presented with hypertrophic cardiomyopathy and Wolff-Parkinson-White (WPW) syndrome at 12 years of age. Subsequently, she showed signs of mild learning disability and intellectual disability on psychological examinations. She had a de novo novel mutation in the LAMP-2 gene and harbored an identical c.749C > A (p.Ser250X) variant, resulting in a stop codon in exon 6. She showed decreased, but not completely absent LAMP-2 expression on immunohistochemical and Western blot analyses of a skeletal muscle biopsy specimen, which has been suggested to be caused by a 50% reduction in LAMP-2 expression (LAMP-2 haploinsufficiency) in female patients with Danon disease caused by a heterozygous null mutation. To our knowledge, our patient is one of the youngest female patients to have been given a diagnosis of Danon disease. In addition, this is the first documented case in a girl that was clearly associated with intellectual disability, which is very rare in females with Danon disease. Our findings suggest that studies of female patients with Danon disease can extend our understanding of the clinical features of this rare disease.
AimCognitive impairment is an important predictor of functional outcome in patients with attention deficit/hyperactivity disorder (ADHD). However, the neurophysiology of ADHD-related cognitive impairments remains unclear. Event-related potentials (ERPs) represent the noninvasive measurement of neural correlates of cognitive function. Mismatch negativity (MMN) is an ERP component that is presumed to index the preattentive monitoring of changes in the auditory environment.Materials and methodsPrevious studies have shown altered MMN amplitude and latency in patients with ADHD. However, little is known about the relationship between MMN and ADHD-symptom severity. To address this, we measured the amplitude and latency of MMN in ERPs and assessed correlations with the clinical severity of ADHD, as measured by the ADHD Rating Scale IV – Japanese version. Participants were 51 treatment-naïve children and adolescents with ADHD (mean age 10.42±3.35 years) and 15 normally developing age- and sex-matched children (mean age 11.8±3.36 years).ResultsIn the ADHD group, MMN amplitudes were attenuated at the central electrode and MMN latencies prolonged at the parietal electrode (Pz) relative to those in the control group. Furthermore, MMN amplitudes at Pz were negatively correlated with ADHD full-scale and hyperactivity–impulsivity and inattention subscale scores, and MMN latency at Pz was positively correlated with ADHD hyperactivity–impulsivity subscale scores.ConclusionOur data suggest that MMN reflects the severity of ADHD symptoms in children and adolescents, and provides support for the use of ERPs in evaluating ADHD symptoms in patients.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.