RESUMO
PagL and LpxO are enzymes that modify lipid A. PagL is a 3-O deacylase that removes the primary acyl chain from the 3 position, and LpxO is an oxygenase that 2-hydroxylates specific acyl chains in the lipid A. pagL and lpxO homologues have been identified in the genome of Bordetella bronchiseptica, but in the current structure for B. bronchiseptica lipid A the 3 position is acylated and 2-OH acylation is not reported. We have investigated the role of B. bronchiseptica pagL and lpxO in lipid A biosynthesis. We report a different structure for wild-type (WT) B. bronchiseptica lipid A, including the presence of 2-OH-myristate, the presence of which is dependent on lpxO. We also demonstrate that the 3 position is not acylated in the major WT lipid A structures but that mutation of pagL results in the presence of 3-OH-decanoic acid at this position, suggesting that lipid A containing this acylation is synthesized but that PagL removes most of it from the mature lipid A. These data refine the structure of B. bronchiseptica lipid A and demonstrate that pagL and lpxO are involved in its biosynthesis.
Assuntos
Proteínas de Bactérias/metabolismo , Bordetella bronchiseptica/enzimologia , Bordetella bronchiseptica/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Lipídeo A/biossíntese , Lipídeo A/química , Oxigenases/metabolismo , Proteínas de Bactérias/genética , Bordetella bronchiseptica/genética , Hidrolases de Éster Carboxílico/genética , Ácidos Láuricos/análise , Miristatos/análise , Oxigenases/genéticaAssuntos
Saúde , Habitação/normas , Comunismo , Fontes de Energia Elétrica , Europa Oriental , Humanos , Problemas SociaisAssuntos
Saúde Ambiental , Implementação de Plano de Saúde/organização & administração , Serviços Preventivos de Saúde/organização & administração , Organização Mundial da Saúde , Europa (Continente) , Política de Saúde , Humanos , Modelos Organizacionais , Objetivos Organizacionais , Avaliação de Programas e Projetos de SaúdeRESUMO
Growing numbers of elderly in countries of the developing world presage an increase in those affected by organic, age-related mental diseases such as dementia. A simultaneous rise in the burden of non-organic mental disorders in elderly populations is likely because stressors in many countries are affecting the mental health of the elderly directly and/or indirectly by altering the ability of families to provide care for them. This paper reviews studies on the disease burden of mental health problems of the aged in the developing world. It examines evidence on how demographic change, economic change, education, urbanization, war and displacement, and widowhood influence elderly mental health. A look at policies and programs improving the condition of elderly mentally ill throughout the developing world emphasizes positive options for policymakers. Recommendations for future research both identify areas in which investigation would be particularly useful and highlight current methodological problems.