Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns. In a survey of 48 countries we found paratuberculosis to be very common in livestock. In about half the countries more than 20% of herds and flocks were infected with MAP. Most countries had large ruminant populations (millions), several types of farmed ruminants, multiple husbandry systems and tens of thousands of individual farms, creating challenges for disease control. In addition, numerous species of free-living wildlife were infected. Paratuberculosis was notifiable in most countries, but formal control programs were present in only 22 countries. Generally, these were the more highly developed countries with advanced veterinary services. Of the countries without a formal control program for paratuberculosis, 76% were in South and Central America, Asia and Africa while 20% were in Europe. Control programs were justified most commonly on animal health grounds, but protecting market access and public health were other factors. Prevalence reduction was the major objective in most countries, but Norway and Sweden aimed to eradicate the disease, so surveillance and response were their major objectives. Government funding was involved in about two thirds of countries, but operations tended to be funded by farmers and their organizations and not by government alone. The majority of countries (60%) had voluntary control programs. Generally, programs were supported by incentives for joining, financial compensation and/or penalties for non-participation. Performance indicators, structure, leadership, practices and tools used in control programs are also presented. Securing funding for long-term control activities was a widespread problem. Control programs were reported to be successful in 16 (73%) of the 22 countries. Recommendations are made for future control programs, including a primary goal of establishing an international code for paratuberculosis, leading to universal acknowledgment of the principles and methods of control in relation to endemic and transboundary disease. An holistic approach across all ruminant livestock industries and long-term commitment is required for control of paratuberculosis. Electronic supplementary material The online version of this article (10.1186/s12917-019-1943-4) contains supplementary material, which is available to authorized users.
Methylocella silvestris BL2, a facultative methane utilizer, can grow on monomethylamine (MMA) as a sole carbon and nitrogen source. No activity of MMA dehydrogenase was detectable. Instead, this bacterium utilizes a methylated amino acid pathway (␥-glutamylmethylamide [GMA] and N-methylglutamate [NMG]) for MMA metabolism. The activities of the two key enzymes in this pathway, GMA synthetase and NMG dehydrogenase, were found when the bacterium was grown on MMA. GMA was detected by high-performance liquid chromatography-mass spectrometry only when the bacterium was grown on MMA but not when it was grown on methanol. Proteomic analysis of soluble and membrane fractions of the proteome from MMA-and methanolgrown cultures revealed that an eight-gene cluster (Msil2632 to Msil2639) was induced by MMA and cotranscribed as an operon, as shown by reverse transcription-PCR. GMA-dissimilating enzyme activity was also detected when it was grown on MMA. Formaldehyde and ammonium production from GMA was dependent on glutamate but not on ␣-ketoglutarate. Marker exchange mutagenesis of a putative GMAS gene homologue (gmas, Msil2635) within this eight-gene cluster, with a kanamycin gene cassette, abolished growth of M. silvestris on MMA as either a sole carbon or a sole nitrogen source. Overall, our results suggest that gmas is essential in MMA metabolism by M. silvestris.Monomethylamine (MMA) is ubiquitous in the environment. For example, putrefaction of proteins (14a, 17) and degradation of many nitrogen-containing pesticides and herbicides can release MMA (5, 16b, 18). In the marine environment, MMA is released from the degradation of quaternary amines, such as betaine, carnitine, choline, and trimethylamine N-oxide, which are used as osmolytes by many marine organisms (3, 6). Once released, MMA can be used by some microorganisms as a sole carbon and nitrogen source through different pathways. Methanogenic archaea, such as Methanosarcina and Methanomicrobium, can use MMA anaerobically as a substrate to produce methane via a methyltransferase system (28). Gram-positive bacteria, such as Arthrobacter, metabolize MMA aerobically via an oxidase, which breaks down MMA into formaldehyde and ammonium (39). Gram-negative bacteria such as Methylobacterium extorquens and Paracoccus denitrificans utilize MMA dehydrogenase, a multisubunit enzyme that generates formaldehyde and ammonium from MMA aerobically (9, 16). Many other Gram-negative bacteria, such as Aminobacter aminovorans (previously known as strain MA and strain MS), can use MMA as a sole carbon and nitrogen source aerobically; however, they lack MMA dehydrogenase. It has been shown that in these microorganisms, two unusual amino acids, ␥-glutamylmethylamide (GMA) and N-methylglutamate (NMG), are involved in MMA metabolism (1,23,33). In strain MA, an enzyme proposed as "NMG synthase" ("NMGS") converted MMA to NMG, which was subsequently oxidized to formaldehyde, regenerating glutamate (Glu) by a membrane-bounded particulate, NMG dehydrogenase (NMGDH) (33). The reactions carrie...
Methylocella silvestris BL2 is an aerobic methanotroph originally isolated from an acidic forest soil in Germany. It is the first fully authenticated facultative methanotroph. It grows not only on methane and other one-carbon (C1) substrates, but also on some compounds containing carbon-carbon bonds, such as acetate, pyruvate, propane, and succinate. Here we report the full genome sequence of this bacterium
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