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Individuals age at vastly different rates resulting in significant within‐population heterogeneity in health and aging outcomes. This diversity in health and aging trajectories has rarely been investigated among low‐income aging populations that have experienced substantial hardships throughout their lifecourses. Utilizing 2006–2019 data from the Malawi Longitudinal Study of Families and Health and estimating group‐based trajectory models, our analyses identified three distinct lifecourse health trajectories: (1) comparatively good initial mental and physical health that persisted throughout the lifecourse ("resilient aging"), (2) relatively good initial mental and physical health that started to deteriorate during mid‐adulthood ("accelerated aging"), and (3) poor initial mental and physical health that further declined over the lifecourse ("aging with persistently poor health"). For both physical and mental health, men were more likely to enjoy resilient aging than women. Predictors other than gender of trajectory membership sometimes confirmed, and sometimes contradicted, hypotheses derived from high‐income country studies. Our analyses highlight the long arm of early life conditions and gender in determining aging trajectories and show that a nontrivial subpopulation is characterized by aging with persistently poor health. The study uncovers widening gaps in health outcomes between those who age with resilience and those who experience accelerated aging. [ABSTRACT FROM AUTHOR]

Studies on global changes in families have greatly increased over the past decade, adopting both a country‐specific and, more recently, a cross‐national comparative perspective. While most studies are focused on the drivers of global changes in families, little comparative research has explored the implications of family processes for the health and well‐being of children. This study aims to fill this gap and launch a new research agenda exploring the intergenerational implications of union‐formation and within‐couple dynamics for children's health and well‐being across low‐ and middle‐income countries (LMICs), both globally, regionally, and by the stage of fertility transition. We do so by adopting a macrolevel perspective and a multi‐axis conceptualization of children's outcomes—health at birth, health in later life, and schooling—and leveraging Demographic and Health Survey and World Bank data across 75 LMICs. Our results show that in societies where partnerships are characterized by more equal status between spouses—that is, where the age range between spouses and differences in years of schooling between partners are narrower—children fare better on several outcomes. These associations are particularly strong in mid‐ and high‐fertility settings. Despite a series of regularities, our results also highlight a set of findings whereby, at a macrolevel, the prevalence of marriage and divorce/separation are not invariably associated with children's outcomes, especially in LMICs where fertility is comparatively lower. We document little cross‐regional heterogeneity, primarily highlighting the centrality of demographic factors such as age vis‐à‐vis, for instance, region‐specific characteristics that are more tied to the social fabric of specific societies. [ABSTRACT FROM AUTHOR]

Background: Research shows that retirement age is associated with later‐life cognition but has not sufficiently distinguished between retirement pathways. We examined how retirement age was associated with later‐life dementia and mild cognitive impairment (MCI) for people who retired via the disability pathway (received a disability pension prior to old‐age pension eligibility) and those who retired via the standard pathway. Methods: The study sample comprised 7210 participants from the Norwegian Trøndelag Health Study (HUNT4 70+, 2017–2019) who had worked for at least one year in 1967–2019, worked until age 55+, and retired before HUNT4. Dementia and MCI were clinically assessed in HUNT4 70+ when participants were aged 69–85 years. Historical data on participants' retirement age and pathway were retrieved from population registers. We used multinomial regression to assess the dementia/MCI risk for women and men retiring via the disability pathway, or early (<67 years), on‐time (age 67, old‐age pension eligibility) or late (age 68+) via the standard pathway. Results: In our study sample, 9.5% had dementia, 35.3% had MCI, and 28.1% retired via the disability pathway. The disability retirement group had an elevated risk of dementia compared to the on‐time standard retirement group (relative risk ratio [RRR]: 1.64, 95% CI 1.14–2.37 for women, 1.70, 95% CI 1.17–2.48 for men). MCI risk was lower among men who retired late versus on‐time (RRR, 0.76, 95% CI 0.61–0.95). Conclusion: Disability retirees should be monitored more closely, and preventive policies should be considered to minimize the dementia risk observed among this group of retirees. Key points: In many countries, a significant proportion of people exit the workforce before they are eligible to receive an old‐age pension due to disability.In a Norwegian population‐based cohort study (based on the HUNT Study linked to population registry data), we found that early retirement due to disability—but not early retirement per se—was associated with a higher risk of dementia in later life.The cognitive health of people exiting the workforce due to disability should be monitored.Studies researching the link between retirement age and later‐life cognition should distinguish between different pathways to retirement. [ABSTRACT FROM AUTHOR]

Research on the timing of events during the transition to adulthood, such as first union, sex, and birth in low- and middle-income countries (LMICs), focused predominantly on measures of central tendency, notably median or mean ages. In this report, we adopt a different perspective on this topic by examining disparities in the timing of these events in 46 LMICs spanning four decades. Using Demographic and Health Surveys, we estimate ages at which 25 percent, 50 percent, and 75 percent of women have first union, birth, and sex. We compute interquartile ranges to measure within-country variation and disparities in the timing of sexual initiation and family formation. Variation in the timing of first union, birth, and sex generally increases as the median ages at these events increase. Disparities in the timing of first union and birth grew in West Africa and Latin America, and women who experience these events relatively early increasingly lag behind women who experience them relatively late. Documenting trends in measures of central tendency is insufficient to capture the complexity of ongoing changes because they mask growing disparities in the timing of family formation across many LMICs. These results are important for assessing progress toward the achievement of sustainable development goals related to the reduction of early marriages and pregnancies and highlight a need for more holistic approaches to measure the timing of family formation. [ABSTRACT FROM AUTHOR]

Using 254 Demographic and Health Surveys from 75 low‐ and middle‐income countries, this study shows how the joint examination of family characteristics across rural and urban areas provides new insights for understanding global family change. We operationalise this approach by building family configurations: a set of interrelated features that describe different patterns of family formation and structure. These features include partnership (marriage/unions) regimes and their stability, gender relations, household composition and reproduction. Factorial and clustering techniques allow us to summarise these family features into three factorial axes and six discrete family configurations. We provide an in‐depth description of these configurations, their spatial distribution and their changes over time. Global family change is uneven because it emerges from complex interplays between the relative steadiness of longstanding arrangements for forming families and organising gender relations, and the rapidly changing dynamics observed in the realms of fertility, contraception, and timing of family formation. [ABSTRACT FROM AUTHOR]

We provide new evidence on the effect of adolescent health behaviors/outcomes (obesity, depression, smoking, and attention deficit hyperactivity disorder [ADHD]) on schooling attainment using the National Longitudinal Study of Adolescent to Adult Health. We take two different approaches to deal with omitted variable bias and reverse causality. Our first approach attends to the issue of reverse causality by estimating the effect of health polygenic scores (PGSs) on schooling. Second, we estimate the effect of adolescent health using sibling fixed‐effects models that control for unmeasured genetic and family factors shared by siblings. We use the PGSs as additional controls in the sibling fixed‐effects models to reduce concerns about residual confounding from sibling‐specific genetic differences. We find consistent evidence across both approaches that being genetically predisposed to smoking and smoking regularly in adolescence reduces schooling attainment. Estimates for depression are more imprecise, but also suggest that a high genetic risk of depression and adolescent depression reduce schooling attainment. We find mixed evidence for ADHD. Our estimates suggest that having a high genetic risk for ADHD reduces grades of schooling, but we do not find any statistically significant negative effects of ADHD. Finally, we find no consistent evidence for a detrimental effect of obesity on schooling attainment. [ABSTRACT FROM AUTHOR]

Objective: This study evaluates whether community norms, caregiver beliefs, and adolescents' own beliefs and perceptions, focused on early marriage, predict adolescent marriage aspirations in a low‐income context. Background: The processes that contribute to adolescent marriage aspiration formation have received little attention in low‐income contexts, particularly sub‐Saharan Africa. Understanding how marriage aspirations are formed is important because they are associated with critical education and health outcomes. Method: Using data that links Malawian adolescents (N = 2089) with their caregivers (N = 1452), gender‐stratified ordered logistic regression models were used to examine key relationships. Results: Results show that community norms for youngest acceptable marriage age predict when boys want to marry, but there is no conclusive evidence that they predict when girls want to marry. This study also shows that adolescents who believe it is acceptable to marry at an early age are more likely to want to marry early themselves. Conclusion: Both community norms and adolescents' own beliefs are central to the formation of their marriage aspirations. Implications: This study recommends that programs incorporate adolescent beliefs and perceptions when designing child marriage interventions and measuring their impact. In addition, theory‐driven measurement of community norms is encouraged to better evaluate their impact on both marriage aspirations and marriage age. [ABSTRACT FROM AUTHOR]

Gender differences in union formation and sexual initiation in sub‐Saharan Africa remain poorly documented, in large part due to a scarcity of research on the transition to adulthood among men. We adopt a novel perspective on this topic by examining gender gaps in the ages at first union and sex in 24 countries, focusing on measures of central tendency and dispersion. Gender differences in age at first union decreased, driven by postponement among women with relatively late union formation. Yet, due to concurrent persistence of early unions among a sizable portion of women's populations, within‐country heterogeneity in ages at first union increased substantially among women. Thus, although forces responsible for earlier union formation among women than men are weakening, these changes affect population strata unequally. Gender differences in age at first sex decreased to a lesser extent, but in some countries, they disappeared or reversed, uncovering a shift in the relationship between gender and timing of sexual initiation. Changes in union formation and sexual initiation are more heterogeneous across countries among men than women, indicating that these processes among men are more context specific. We show importance of studying men's behavior and exploring heterogeneity in union formation and sexual initiation both within and between populations of women and men. [ABSTRACT FROM AUTHOR]

Despite an extensive literature on the psychological rewards of marriage and children in high‐income countries, research on these relationships in low‐income countries remains limited. This paper draws on data from 4,133 adult women and men interviewed in the Malawi Longitudinal Study of Families and Health to examine how marital status, categorized as never, formerly, monogamously, and polygynously married, and number of children are associated with psychological well‐being. With respect to marital status, we find that women in polygynous unions fare worse than monogamously married women and this detrimental effect is stronger for women than for men. Formerly married men and women of reproductive age experience the worst psychological outcomes, although this association wanes with age. In contrast, the benefits of having children is only evident among older Malawian women. These findings offer novel insights into the patterns of nearly universal marriage and high fertility that characterize Malawi and much of sub‐Saharan Africa. [ABSTRACT FROM AUTHOR]

The article focuses on contributions to the literature on intergenerational transfers and investigate patterns of financial and non-financial transfers by drawing on rich longitudinal data from rural Malawi. It mentions important insights into the micro-level dynamics of intergenerational economics in a low-resource setting and patterns using fixed-effects regression models. It also mentions National Transfer Accounts (NTA) has limited applicability and social protection schemes.

We have shown for the first time that a natural protein (human insulin) can be acylated at the N‐terminus with a β‐amino acid (H‐β3hAla‐), in a process catalyzed by the β‐peptidyl aminopeptidase 3‐2W4‐BapA. This selective modification, which could also be applied for protein labeling and tagging, should be generally useful, also to protect peptides and proteins from attack by common aminopeptidases. [ABSTRACT FROM AUTHOR]

Rationale Oxygen isotope fractionation of molecular O2 is an important process for the study of aerobic metabolism, photosynthesis, and formation of reactive oxygen species. The latter is of particular interest for investigating the mechanism of enzyme-catalyzed reactions, such as the oxygenation of organic pollutants, which is an important detoxification mechanism. Methods We developed a simple method to measure the δ18O values of dissolved O2 in small samples using automated split injection for gas chromatography coupled to isotope ratio mass spectrometry (GC/IRMS). After creating a N2 headspace, the dissolved O2 partitions from aqueous solution to the headspace, from which it can be injected into the gas chromatograph. Results In aqueous samples of 10 mL and in diluted air samples, we quantified the δ18O values at O2 concentrations of 16 μM and 86 μM, respectively. The chromatographic separation of O2 and N2 with a molecular sieve column made it possible to use N2 as the headspace gas for the extraction of dissolved O2 from water. We were therefore able to apply a rigorous δ18O blank correction for the quantification of 18O/16O ratios in 20 nmol of injected O2. Conclusions The successful quantification of 18O-kinetic isotope effects associated with enzymatic and chemical reduction of dissolved O2 illustrates how the proposed method can be applied for studying enzymatic O2 activation mechanisms in a variety of (bio)chemical processes. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

While new empirical findings and theoretical frameworks provide insight into the interrelations between socioeconomic development, gender equity, and low fertility, puzzling exceptions and outliers in these findings call for a more all-encompassing framework to understand the interplay between these processes. We argue that the pace and onset of development are two important factors to be considered when analyzing gender equity and fertility. Within the developed world, 'first-wave developers'-or countries that began socioeconomic development in the nineteenth/early twentieth century-currently have much higher fertility levels than 'late developers.' We lay out a novel theoretical approach to explain why this is the case and provide empirical evidence to support our argument. Our approach not only explains historical periods of low fertility but also sheds light on why there exists such large variance in fertility rates among today's developed countries. [ABSTRACT FROM AUTHOR]

Although the production and use of technical hexachlorocyclohexane ( HCH) and lindane (the purified insecticidal isomer γ- HCH) are prohibited in most countries, residual concentrations still constitute an immense environmental burden. Many studies describe the mineralization of γ- HCH by bacterial strains under aerobic conditions. However, the metabolic fate of the other HCH isomers is not well known. In this study, we investigated the transformation of α-, β-, γ-, δ-, ε- HCH, and a heptachlorocyclohexane isomer in the presence of varying ratios of the two enzymes that initiate γ- HCH degradation, a dehydrochlorinase ( LinA) and a haloalkane dehalogenase ( LinB). Each substrate yielded a unique metabolic profile that was strongly dependent on the enzyme ratio. Comparison of these results to those of in vivo experiments with different bacterial isolates showed that HCH transformation in the tested strains was highly optimized towards productive metabolism of γ- HCH and that under these conditions other HCH-isomers were metabolized to mixtures of dehydrochlorinated and hydroxylated side-products. In view of these results, bioremediation efforts need very careful planning and toxicities of accumulating metabolites need to be evaluated. [ABSTRACT FROM AUTHOR]

β-Peptides and their derivates are usually stable to proteolysis and have an increased half-life compared with α-peptides. Recently, β-aminopeptidases were described as a new enzyme class that enabled the enzymatic degradation and formation of β-peptides. As an alternative to the existing chemical synthesis routes, the aim of the present work was to develop a whole-cell biocatalyst for the synthesis and production of β-peptides using this enzymatic activity. For the optimization of the reaction system we chose the commercially relevant β, α-dipeptidel-carnosine ( β-alanine-l-histidine) as model product. We were able to show that different recombinant yeast and bacteria strains, which overexpress a β-peptidase, could be used directly as whole-cell biocatalysts for the synthesis ofl-carnosine. By optimizing relevant reaction conditions for the best-performing recombinant Escherichia coli strain, such as pH and substrate concentrations, we obtained highl-carnosine yields of up to 71%. Long-time as well as biocatalyst recycling experiments indicated a high stability of the developed biocatalyst for at least five repeated batches. Application of the recombinant E. coli in a fed-batch process enabled the accumulation ofl-carnosine to a concentration of 3.7 g l−1. [ABSTRACT FROM AUTHOR]

We explore how marital aspirations are related to the sexual behaviors of adolescents and young adults in Malawi, where HIV/AIDS prevalence among adults exceeds 10%. We also consider whether the specter of AIDS is shaping ideals about marriage. By combining survey data (N = 1,087) and in-depth interviews (N = 133) with young Malawians from the Malawi Diffusion and Ideational Change Project, we show that looking for and finding a suitable spouse are linked to sexual behaviors and, thus, HIV risks. Moreover, concerns about contracting HIV are closely tied to the ideal characteristics of a future spouse. Our findings draw long-overdue attention to the importance of marital aspirations in understanding adolescent sexual behaviors and risks in the era of AIDS. [ABSTRACT FROM AUTHOR]

This article discusses how European women are historically bearing their first children later than ever before. In the United States and other countries, entry into parenthood is also seeing delays. Many experts argue that such fertility trends in developed countries are characterized by increasing, persistent, and arguably irreversible delays in childbearing in many socioeconomic conditions. Many of the informal age deadlines for childbearing are apparently being challenged and biological limits are being pushed. The article also presents information about the physiological aspects of late fertility and discusses the effect of new technologies on conception and pregnancy. Sweden's late and very late fertility is also examined.

We previously discovered that BapA, a bacterial β-peptidyl aminopeptidase, is able to hydrolyze two otherwise metabolically inert β-peptides [Geueke B, Namoto K, Seebach D & Kohler H-PE (2005) J Bacteriol 187, 5910–5917]. Here, we describe the purification and characterization of two distinct bacterial β-peptidyl aminopeptidases that originated from different environmental isolates. Both bapA genes encode a preprotein with a signal sequence and were flanked by ORFs that code for enzymes with similar predicted functions. To form the active enzymes, which had an (αβ)4 quaternary structure, the preproteins needed to be cleaved into two subunits. The two β-peptidyl aminopeptidases had 86% amino acid sequence identity, hydrolyzed a variety of β-peptides and mixed β/α-peptides, and exhibited unique substrate specificities. The prerequisite for peptides being accepted as substrates was the presence of a β-amino acid at the N-terminus; peptide substrates with an N-terminal α-amino acid were not hydrolyzed at all. Both enzymes cleaved the peptide bond between the N-terminal β-amino acid and the amino acid at the second position of tripeptidic substrates of the general structure H-βhXaa-Ile-βhTyr-OH according to the following preferences with regard to the side chain of the N-terminal β-amino acid: aliphatic and aromatic > OH-containing > hydrogen, basic and polar. Experiments with the tripeptides H-d-βhVal-Ile-βhTyr-OH and H-βhVal-Ile-βhTyr-OH demonstrated that the two BapA enzymes preferred the peptide with thel-configuration of the N-terminal β-homovaline residue as a substrate. [ABSTRACT FROM AUTHOR]

This paper reviews several studies that investigated the potential role of genetic factors in determining fertility outcomes. Our review demonstrates convincingly that fertility contains genetic variance; that is, differences between humans in their genetic make-up affects their fertility outcomes and fertility-related behaviours. This finding is robust using both heritabilities and coefficients of genetic variation, and using both direct measures of fertility outcomes and also fertility precursors like fecundity, marriage, fertility expectations and attempts to get pregnant (proception). Moreover, genetic variance can change over short periods of time or across educational levels, specifically for females, and the relevance of genetic variance seems to increase during times of increasing reproductive choice. [ABSTRACT FROM AUTHOR]

Economic and rational-choice theories suggest that individuals form unions or have children because these decisions increase their subjective well-being or “happiness.” We investigate this relation using within-MZ (identical) twin pair estimates to control for unobserved factors, such as optimistic preferences, that may simultaneously affect happiness, partnerships, and fertility. Our findings, based on Danish twins aged 25–45 and 50–70 years old, include the following. (1) Currently being in a partnership has large positive effects on happiness. (2) A first child substantially increases well-being, in analyses without controls for partnerships, and males enjoy an almost 75 percent larger happiness gain from a first-born son than from a first-born daughter; however, only females enjoy a happiness gain from the first-born child with controls for partnerships. (3) Additional children beyond the first child have a negative effect on subjective well-being for females, while there is no effect for males. (4) Ever having had children does not significantly affect the subjective well-being of males or females aged 50–70 years. [ABSTRACT FROM AUTHOR]

Lowest-low fertility, defined as a period total fertility rate at or below 1.3, has rapidly spread in Europe during the 1990s. This article traces the emergence of this new phenomenon to the interaction of five factors. First, tempo and compositional distortions reduce the total fertility rate below the associated level of cohort fertility. Second, socioeconomic changes--including increased returns to human capital and high economic uncertainty in early adulthood--have made late childbearing a rational response for individuals and couples. Third, social interaction effects reinforce this behavioral adjustment and contribute to large and persistent postponement in the mean age at birth. Fourth, institutional settings favor an overall low quantum of fertility. Fifth, postponement-quantum interactions amplify the consequences of this institutional setting when combined with ongoing delays of childbearing. The article concludes with speculations about future trends in current and prospective lowest-low-fertility countries. [ABSTRACT FROM AUTHOR]

This article investigates the fertility of Danish twins born during the periods 1870-1910 and 1953-64 in order to pursue two central questions for understanding human reproduction: Do genetic dispositions influence fertility and fertility-related behavior? Does the relevance of the "nature versus nurture" debate shift over time or with demographic regimes? The authors find that genetic influences on fertility exist, but that their relative magnitude and pattern are contingent on gender and on the socioeconomic environment experienced by cohorts. Among females born in 1880-90 and after 1955, about 30-50 percent of the variance in fertility is due to genetic influences; these influences are substantially smaller for earlier and for interim birth cohorts. Male fertility is generally subject to smaller genetic and larger shared-environment effects than female fertility. Because genetic effects are most prevalent in situations with deliberately controlled fertility and relatively egalitarian socioeconomic opportunities, the authors propose that the genetic dispositions affect primarily fertility behavior and motivations for having children. Analyses of fertility motivations, measured by age of first attempt to have a child, support this interpretation. [ABSTRACT FROM AUTHOR]

Analyzes the effect of hedonic migration decisions and regional amenities on industrial location, focusing on the geography of economic regions. Description of the theoretical model used to study the interdependence between migration, regional amenities and industrial location; Identification of three distinct location patterns; Explanation associated with patterns.

The sulfate-reducing bacteria Desulfobacterium autotrophicum. Desulfobulbus propionicus and Archaeoglobus fulgidus (VC-16) and the sulfur-metabolizing archaebacteria Desulfurolobus ambivalens and Thermoplasma acidophilum were found to contain considerable amounts of corrinoids, that were isolated and crystallized in their Coβ-cyano form. In three other sulfur-metabolizing archaebacteria, Thermoproteus neutrophilus, Pyrodictium occultum and Staphylothermus marinus significant amounts of corrinoids were not detected under the isolation methods used. The samples from the three sulfate-reducers were identified with Coα-[α-(5'-methylbenzimidazolyl)]-Coβcyanocobamide. This corrinoid was also obtained from a 5-methylbenzimidazole-supplemented Propionibacterium fermentation and was structurally characterized by ultraviolet/visible, CD, fast-atom-bombardment MS, ¹H- and 13C-NMR spectroscopy. Also the major corrinoid from T. acidophilum was (tentatively) analyzed as a 5'-methylbenzimidazolyl-cobamide, whereas the main corrinoid from D. ambivalens was indicated to be vitamin B12 (a 5',6'-dimethylbenzimidazolyl-cobamide). The 5'-methylbenzimidazolylcobamides are found here as the common corrins of some sulfate-reducing and sulfur-metabolizing bacteria. The structural diversity due to the differing nucleotide bases of the coffins examined here and in methanogenic and acetogenic bacteria appears not to correlate to the biological function(s) of the corrins, but rather to be determined by biosynthetic properties of these organisms under natural growth conditions. [ABSTRACT FROM AUTHOR]

2-Hydroxybiphenyl 3-monooxygenase (HbpA; EC 1.14.13.44) from Pseudomonas azelaica HBP1 was produced in Escherichia coli both as native and SeMet-labelled protein. The two enzymes were purified to homogeneity and crystallized by the hanging-drop vapour diffusion method. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 108.6, b = 196.8, c = 79.3 Å, β = 97.7° for the native protein and a = 108.3, b = 196.8, c = 79.0 Å, β = 97.8° for SeMet HbpA. Crystal-packing considerations led to the assumption of two HbpA subunits per asymmetric unit, which corresponds to a V[sub M] value of 3.3 ų Da[sup -1] and a solvent content of 62%. The crystals were radiation-sensitive and only had a lifespan of about 120 s when exposed to synchrotron radiation on an undulator beamline. To obtain complete data sets, data were collected from 23 native and 26 derivative crystals. The high-resolution limit was 2.0 Å for native and 2.25 Å for SeMet HbpA. [ABSTRACT FROM AUTHOR]

β-Peptides and their derivates are usually stable to proteolysis and have an increased half-life compared with α-peptides. Recently, β-aminopeptidases were described as a new enzyme class that enabled the enzymatic degradation and formation of β-peptides. As an alternative to the existing chemical synthesis routes, the aim of the present work was to develop a whole-cell biocatalyst for the synthesis and production of β-peptides using this enzymatic activity. For the optimization of the reaction system we chose the commercially relevant β,α-dipeptide L-carnosine (β-alanine-L-histidine) as model product. We were able to show that different recombinant yeast and bacteria strains, which overexpress a β-peptidase, could be used directly as whole-cell biocatalysts for the synthesis of L-carnosine. By optimizing relevant reaction conditions for the best-performing recombinant Escherichia coli strain, such as pH and substrate concentrations, we obtained high l-carnosine yields of up to 71%. Long-time as well as biocatalyst recycling experiments indicated a high stability of the developed biocatalyst for at least five repeated batches. Application of the recombinant E. coli in a fed-batch process enabled the accumulation of l-carnosine to a concentration of 3.7 g l(-1)., (© 2009 The Authors. Journal compilation © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.)