Methylotrophic bacteria methylotrophs

Methoxatin, now known as coenzyme PQQ, was originally obtained from methylotrophic bacteria but is now known to be a mammalian cofactor, for example, for lysyl oxidase and dopamine p-hydroxylase. The first synthesis of this rare compound was accomplished by the route outlined below. In the retrosynthetic analysis both of the heterocyclic rings were disconnected using directly keyed transforms. 

Bacteria Heterotroph (methylotroph) Hydrocarbon derivatives (methanol) As carbon source NHs, NH4+... 

A few of the reactions carried out by the monooxygenase system of methanotrophic bacteria are summarized in Figure 2.9, and it is on account of this that methylotrophs have received attention for their technological potential (Lidstrom and Stirling 1990). An equally wide metabolic potential has also been demonstrated for cyclohexane monooxygenase, which has been shown to accomplish two broad types of reaction one in which formally nucleophilic oxygen reacts with the substrate, and... 

The degradation of trichloroethene by methylotrophic bacteria involves the epoxide as intermediate (Little et al. 1988). Further transformation of this may produce CO that can toxify the bacterium, both by competition for reductant and by enzyme inhibition (Henry and Grbic-Galic 1991). The inhibitory effect of CO may, however, be effectively overcome by adding a reductant such as formate. 

Lidstrom-O Connor ME, GL Fulton, AE Wopat (1983) Methylobacterium ethanolicum a syntrophic association of two methylotrophic bacteria. J Gen Microbiol 129 3139-3148. 

Chistoserdova L, JA Vorholt, RK Thauer, ME Lidstrom (1998) Cl transfer enzymes and coenzymes linking methylotrophic bacteria and methanogenic archaea. Science 281 99-102. 

Kohler-Staub D, S Hartmans, R Galli, F Suter, T Leisinger (1986) Evidence for identical dichloromethane dehalogenases in different methylotrophic bacteria. J Gen Microbiol 132 2837-2843. 

Strains of some facultatively heterotrophic and methylotrophic bacteria can use CS2 as sole energy source, and under aerobic conditions also COS, dimethyl sulfide, dimethyl disulfide, and thioacetate (Jordan et al. 1995). It was proposed that the strains belonged to the genus Thiobacillus, though they are clearly distinct from previously described species, and they have now been assigned to Paracoccus denitrificans (Jordan et al. 1997). 

Various other bacterial strains and processes have been studied by academic groups for the production of poly(3HB) or poly(3HB-co-3HV), several of which are presented here. Some methylotrophic and methanotrophic bacteria are interesting for poly(3HB) production purposes. Methanol is an inexpensive substrate and there is considerable experience in methanol fermentation techno-... 

Two amicyanins have been a recent focus of attention [84, 85], These are from the methylotrophic bacteria Pseudomonas AMI and Thiobacillus versutus,... 

A phylogenetic analysis of H4MPT-dependent enzymes reveals distinct archaeal and bacterial branches of the tree that are clearly related however, the results still do not resolve whether a common ancestor contained H4MPT-dependent enzymes or the methylotrophs acquired genes from the Archaea domain. Nonetheless, analysis of the genomic sequences from the Bacteria domain indicate that only the methylotrophic proteobacteria harbor HiMPT-dependent enzymes are consistent with lateral transfer from archaeal donors (Vorholt et al. 1999). 

Vorholt JA, Chistoserdova L, Stolyar SM, et al. 1999. Distribution of tetrahy-dromethanopterin-dependent enzymes in methylotrophic bacteria and phylogeny of methenyl tetrahydromethanopterin cyclohydrolases. J Bacteriol 181 5750-7. 

Some methylotrophic bacteria dehydrogenate methanol to formaldehyde. The latter undergoes an aldol condensation to form a hexulose-6-phos-phate ... 

Bacteria that oxidize methane or methanol (methylotrophs) employ a periplasmic methanol dehydrogenase that contains as a bound coenzyme, the pyrroloquinoline quinone designated PQQ or meth-oxatin (Eq. 15-51).442 I 1 1 This fluorescent ortfzo-quinone... 

Hydroxylases with properties similar to those of cytochrome P450 but containing nonheme iron catalyze co-oxidation of alkanes and fatty acids in certain bacteria, e.g., Pseudomonas oleovarans. A flavoprotein rubredoxin reductase, is also required.501 The methylotrophs Methylococcus and Methylosinus hydroxylate methane using as cosubstrate NADH or NADPH (Eq. 18-59). A soluble complex consists of 38-kDa reductase containing FAD and an Fe2S2... 

When FI is replaced by PQQ (pyrroloquinolinequinone), a novel heterocyclic o-quinone cofactor that was first isolated and identified from methanol dehydrogenase of methylotrophic bacteria in 1979 [68], the photochemical oxidation of benzyl alcohols occurs efficiently without HC104 in MeCN [69] ... 

Pyrroloquinolinequinone (213) (2,7,9-tricarboxy-l/7-pyrrolo[2,3-/]quinoline-4,5-dione, PQQ) (trivial name methoxatin) has been identified as a co-factor in many enzymes, including those that oxidize MeOH to HCHO in methylotrophic and autotrophic bacteria. Quinoproteins appear in mammalian systems as well, and methoxatin itself (213) has even been identified as an inhibitor of HIV-1 reverse transcriptase (for PQQ reviews, see <91MI 722-02, 95MI 722-02)). Interest in under-... 

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