scholarly journals Trimethylamine metabolism in obligate and facultative methylotrophs

1973 ◽  
Vol 132 (1) ◽  
pp. 101-112 ◽  
Author(s):  
J. Colby ◽  
L. J. Zatman

1. Twelve bacterial isolates that grow with trimethylamine as sole source of carbon and energy were obtained in pure culture. All the isolates grow on methylamine, dimethylamine and trimethylamine. One isolate, bacterium 4B6, grows only on these methylamines whereas another isolate, bacterium C2A1, also grows on methanol but neither grows on methane; these two organisms are obligate methylotrophs. The other ten isolates grow on a variety of Ci and other organic compounds and are therefore facultative methylotrophs. 2. Washed suspensions of the obligate methylotrophs bacteria 4B6 and C2A1, and of the facultative methylotrophs bacterium 5B1 and Pseudomonas 3A2, all grown on trimethylamine, oxidize trimethylamine, dimethylamine, formaldehyde and formate; only bacterium 5B1 and Ps. 3A2 oxidize trimethylamine N-oxide; only bacterium 4B6 does not oxidize methylamine. 3. Cell-free extracts of trimethylamine-grown bacteria 4B6 and C2A1 contain a trimethylamine dehydrogenase that requires phenazine methosulphate as primary hydrogen acceptor, and evidence is presented that this enzyme is important for the growth of bacterium 4B6 on trimethylamine. 4. Cell-free extracts of eight facultative methylotrophs, including bacterium 5B1 and Ps. 3A2, do not contain trimethylamine dehydrogenase but contain instead a trimethylamine monooxygenase and trimethylamine N-oxide demethylase. It is concluded that two different pathways for the oxidation of trimethylamine occur amongst the isolates.

1974 ◽  
Vol 143 (3) ◽  
pp. 555-567 ◽  
Author(s):  
John Colby ◽  
Leonard J. Zatman

1. The trimethylamine dehydrogenase of bacterium 4B6 was purified to homogeneity as judged by analytical polyacrylamide-gel electrophoresis. The specific activity of the purified enzyme is 30-fold higher than that of crude sonic extracts. 2. The molecular weight of the enzyme is 161000. 3. The kinetic properties of the purified enzyme were studied by using an anaerobic spectrophotometric assay method allowing the determination of trimethylamine dehydrogenase activity at pH8.5, the optimum pH. The apparent Km for trimethylamine is 2.0±0.3μm and the apparent Km for the primary hydrogen acceptor, phenazine methosulphate, is 1.25mm. 4. Of 13 hydrogen acceptors tested, only Brilliant Cresyl Blue and Methylene Blue replace phenazine methosulphate. 5. A number of secondary and tertiary amines with N-methyl and/or N-ethyl groups are oxidized by the purified enzyme; primary amines and quaternary ammonium salts are not oxidized. Of the compounds that are oxidized by the purified enzyme, only trimethylamine and ethyldimethylamine support the growth of bacterium 4B6. 6. Trimethylamine dehydrogenase catalyses the anaerobic oxidative N-demethylation of trimethylamine with the formation of stoicheiometric amounts of dimethylamine and formaldehyde. Ethyldimethylamine is also oxidatively N-demethylated yielding ethylmethylamine and formaldehyde; diethylamine is oxidatively N-de-ethylated. 7. The activity of the purified enzyme is unaffected by chelating agents and carbonyl reagents, but is inhibited by some thiol-binding reagents and by Cu2+, Co2+, Ni2+, Ag+ and Hg2+. Trimethylamine dehydrogenase activity is potently inhibited by trimethylsulphonium chloride, by tetramethylammonium chloride and other quaternary ammonium salts, and by monoamine oxidase inhibitors of the substituted hydrazine and the non-hydrazine types. 8. Inhibition by the substituted hydrazines is time-dependent, is prevented by the presence of trimethylamine or trimethylamine analogues and in some cases requires the presence of the hydrogen acceptor phenazine methosulphate. The inhibition was irreversible with the four substituted hydrazines that were tested.


2000 ◽  
Vol 66 (2) ◽  
pp. 566-570 ◽  
Author(s):  
Mitsunori Tarao ◽  
Masayuki Seto

ABSTRACT The yield coefficient (YC) of Pseudomonas sp. strain DP-4, a 2,4-dichlorophenol (DCP)-degrading organism, was estimated from the number of CFU produced at the expense of 1 unit amount of DCP at low concentrations. At a low concentration of DCP, the YC can be overestimated in pure culture, because DP-4 assimilated not only DCP but also uncharacterized organic compounds contaminating a mineral salt medium. The concentration of these uncharacterized organic compounds was nutritionally equivalent to 0.7 μg of DCP-C ml−1. A mixed culture with non-DCP-degrading organisms resulted in elimination of ca. 99.9% of the uncharacterized organic compounds, and then DP-4 assimilated only DCP as a substrate. In a mixed culture, DP-4 degraded an initial concentration of 0.1 to 10 μg of C ml of DCP−1 and the number of CFU of DP-4 increased. In the mixed culture, DCP at an initial concentration of 0.07 μg of C ml−1 was degraded. However, the number of CFU of DP-4 did not increase. DCP at an extremely low initial concentration of 0.01 μg of C ml−1 was not degraded in mixed culture even by a high density, 105 CFU ml−1, of DP-4. When glucose was added to this mixed culture to a final concentration of 1 μg of C ml−1, the initial concentration of 0.01 μg of C ml of DCP−1 was degraded. These results suggested that DP-4 required cosubstrates to degrade DCP at an extremely low initial concentration of 0.01 μg of C ml−1. The YCs of DP-4 at the expense of DCP alone decreased discontinuously with the decrease of the initial concentration of DCP, i.e., 1.5, 0.19, or 0 CFU per pg of DCP-C when 0.7 to 10, 0.1 to 0.5, or 0.07 μg of C ml of DCP−1 was degraded, respectively. In this study, we developed a new method to eliminate uncharacterized organic compounds, and we estimated the YC of DP-4 at the expense of DCP as a sole source of carbon.


1973 ◽  
Vol 8 (1) ◽  
pp. 110-121
Author(s):  
A. Netzer ◽  
J.D. Norman

Abstract The merits of activated carbon for removal of organic compounds from wastewater have been well documented in the literature. On the other hand there is a lack of published data on the use of activated carbon for the removal of trace metals from wastewater. Experiments were designed to assess the possibility that activated carbon treatment would remove aluminum, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, silver and zinc from wastewater. All metals studied were tested over the pH range 3-11. Greater than 99.5% removal was achieved by pH adjustment and activated carbon treatment for most of the metals tested.


1996 ◽  
Vol 34 (10) ◽  
pp. 67-72 ◽  
Author(s):  
Lu Chih-Jen ◽  
Lee Chi-Mei ◽  
Huang Chiou-Zong

The biodegradation of phenol and chlorophenols by immobilized pure-culture cells was conducted by a series of batch reactors. The microorganisms used in this study were Pseudomonas putida, Psuedomonas testosteroni, Pseudomonas aeruginosa, and Agrobacterium radiobacter. All four species showed the ortho-cleavage pathway to metabolize chlorophenols. Among the four species, P. testosteroni, P. putida, and P. aeruginosa could effectively remove phenol at 200 mg/l. P. testosteroni could effectively remove 2-chlorophenol at 10mg/l. However, the other three species, P. putida, P. aeruginosa, and A. radiobacter, could not effectively remove 2-chlorophenol. Although 3-chlorophenol is a recalcitrant compound, P. testosteroni also could rapidly metabolize 3-chlorophenol at 10 mg/l. The removal of 4-chlorophenol at 10 mg/l by P. testosteroni reached 98% within one day. P. aeruginosa and A. radiobacter also could metabolize 4-chlorophenol after 2 and 7 days of lag period, respectively.


1937 ◽  
Vol 10 (1) ◽  
pp. 158-163
Author(s):  
W. Langenbeck ◽  
H. C. Rhiem

Abstract The catalytic power of organic compounds in general has up to the present time been studied much less extensively than that of inorganic compounds. For about the last ten years, however, the first author has, in collaboration with a number of his students, attempted to fill this gap, though so far efforts have been confined to explaining the mode of action of natural enzymes by means of comparative experiments with organic catalysts. As a result of this work, a theory based on experimental facts has been developed to explain in a satisfactory way the action of enzymes. The other phase of organic catalysis is, strictly speaking, a technical problem. Why for instance should it not be practicable to utilize organic catalysts more extensively than heretofore in industry? If this problem is to be attacked, it seems reasonable to start with the particular industry which already uses organic catalysts to the greatest extent. This is, of course, the rubber industry. The important accomplishments of the chemical industry with respect to the development of vulcanization accelerators is already common knowledge, and the important task at present is not simply to increase the great number of accelerators already known. A problem of more practical value would seem to be to study the mechanism of the acceleration of vulcanization, about which relatively little has been known heretofore.


Author(s):  
Felix Emele Emele ◽  
Kehinde Caleb Daramola ◽  
Arthur Ebelenna Anyabolu

Respiratory cryptococcosis caused by Cryptococcus species can present with symptoms indistinguishable from bacterial or viral etiology. Cryptococcus species produce typical colonial features on Sunflower Seed Agar (SSA), which aids in rapid diagnoses of cryptococcosis. In studying respiratory cryptococcosis, we observed bacterial growths on SSA that resembled Cryptococcus species in colonial characteristics. This study aimed at identifying and characterizing those bacterial isolates for documentation. Sputum samples were collected from 201 patients with symptoms suggestive of respiratory cryptococcosis. The samples were inoculated onto SSA, incubated at 37oC for two weeks. Suspected colonies were further evaluated. Of the samples, none yielded Cryptococcus species, although a total of twenty Cryptococcus-resembling bacterial colonies were encountered and isolated. Eight of the isolates could not amplify by PCR techniques. The other twelve were identified as follows: Klebsiella pneumonia (8 or 67%), Klebsiella ozaneae (3 or 25%), and Enterobacter ludwigii (1 or 8%). All isolates were susceptible to Ertapenem, Meropenem, and Fosfomycin but resistant to ampicillin. Results show that Klebsiella and Enterobacter pneumonia-like illnesses can be misidentified as cryptococcosis using SSA.  Reliance on microscopic rather than macroscopic, colonial features on SSA will prevent misdiagnosis.


1963 ◽  
Vol 46 (4) ◽  
pp. 559-564
Author(s):  
Al Steyermakk

Abstract A specific gravimetric procedure was submitted to the collaborators for this year’s study on the determination of oxygen in organic compounds. Three compounds were analyzed: one contained no oxygen, one contained only carbon, hydrogen, and oxygen, and the other was a sulfa compound. The results obtained were good, and the method is recommended as official, first action.


2002 ◽  
Vol 68 (8) ◽  
pp. 3867-3872 ◽  
Author(s):  
Kohtaro Kirimura ◽  
Toshiki Furuya ◽  
Rika Sato ◽  
Yoshitaka Ishii ◽  
Kuniki Kino ◽  
...  

ABSTRACT Naphtho[2,1-b]thiophene (NTH) is an asymmetric structural isomer of dibenzothiophene (DBT), and in addition to DBT derivatives, NTH derivatives can also be detected in diesel oil following hydrodesulfurization treatment. Rhodococcus sp. strain WU-K2R was newly isolated from soil for its ability to grow in a medium with NTH as the sole source of sulfur, and growing cells of WU-K2R degraded 0.27 mM NTH within 7 days. WU-K2R could also grow in the medium with NTH sulfone, benzothiophene (BTH), 3-methyl-BTH, or 5-methyl-BTH as the sole source of sulfur but could not utilize DBT, DBT sulfone, or 4,6-dimethyl-DBT. On the other hand, WU-K2R did not utilize NTH or BTH as the sole source of carbon. By gas chromatography-mass spectrometry analysis, desulfurized NTH metabolites were identified as NTH sulfone, 2′-hydroxynaphthylethene, and naphtho[2,1-b]furan. Moreover, since desulfurized BTH metabolites were identified as BTH sulfone, benzo[c][1,2]oxathiin S-oxide, benzo[c][1,2]oxathiin S,S-dioxide, o-hydroxystyrene, 2-(2′-hydroxyphenyl)ethan-1-al, and benzofuran, it was concluded that WU-K2R desulfurized NTH and BTH through the sulfur-specific degradation pathways with the selective cleavage of carbon-sulfur bonds. Therefore, Rhodococcus sp. strain WU-K2R, which could preferentially desulfurize asymmetric heterocyclic sulfur compounds such as NTH and BTH through the sulfur-specific degradation pathways, is a unique desulfurizing biocatalyst showing properties different from those of DBT-desulfurizing bacteria.


1979 ◽  
Vol 8 ◽  
pp. 163-175 ◽  
Author(s):  
J. E. Cross

After almost a century of discussion of the traditions about the apostles in Cynewulf's poem it is somewhat surprising to find that some simple literary contacts have been ignored. This is true of the latest edition of the poem and of the more recent book,Sources and Analogues of Old English Poetry. In an earlier edition G. P. Krapp had chosen Bede'sMartyrologyas a source forFates, but, since Dom Quentin's detailed work on historical martyrologies has excised the accretions which that martyrology has accumulated, the authentic Bede can now be left out of the discussion. In modern times it seems that two lists of apostles which preface the Hieronymian Martyrology in eighth-century manuscripts are regarded as analogues or contributory sources. These are theNotitia de locis Apostolorum (Notit.), a list of the apostles’ resting-places, in the Echternach manuscript, and theBreviarium Apostolorum (Brev.), in other manuscripts. The two tracts entitledDe Ortu et Obitu Patrumin Migne's Patrologia Latina, the one normally assigned to Isidore of Seville(IO)and the other now regarded as an anonymous Hiberno-Latin tract(HLO)from the eighth century, and both including the apostles, have been considered by previous scholars. All these four works are early enough to have been consulted by Cynewulf, who is thought to have been writing in the ninth century, but none of them individually nor all of them collectively could have provided Cynewulf with all his factual details: none of them reports that James Zebedaei died ‘mid Iudeum’ (35 a) (although this fact could be assumed fromBrev., IOandHLO, which state that he was killed by Herod), that Philip preached in Asia (38a), that Thomas raised Gad, the king's brother, from death and that he himself was killed by a sword (54–60), that Matthew preached in Ethiopia (64) and that a named king ‘Irtacus’ (68a) ordered him to be slain ‘wæpnum’ (69b), that Simon and Thaddeus (or Jude) went together to Persia (76b) and that they died on the same day (‘him wearð bam samod / an endedæg‘, 78b–9a). These details are all lacking inHLO, which has the least differences from Cynewulf's poem. Each of the other texts individually has other differences,Notit. having the greatest number. These abbreviated accounts, of course, merely transmit traditions about the apostles, and so it is clear that Cynewulf used different traditions for at least Philip, Thomas, Matthew and the pair Simon and Thaddeus, who are linked by Cynewulf, whereas in the other texts either they are separated or Thaddeus is not mentioned. It is possible that a curious assumption of ‘short poem, short source’ has prevented scholars from being alert to the significance of a clear clue which has long been available. In Brooks's edition we read that ‘the resurrection of Gad… is not mentioned in Bede'sMartyrology, nor in theBreviarium; hence neither of these can be the sole source of the poem. A full account is given in the Apocryphal Acts of Thomas’, in other words, in the full story of Thomas'sPassio. I hope to demonstrate that almost all the details about the apostles in the poem came immediately from the full stories of theVitaeorPassioneswhich are still extant. In my opinion it is unnecessary to consider the possibility of an abbreviated intermediary, since, as a religious of his period Cynewulf would have heard stories of the saints, including the apostles, on their feast-days, and, as we know, he had access to written accounts for two pieces for such festivals, a story of theInventio Crucisfor his poemEleneand aVita S. Julianaefor his poem under her name. He would have been remarkably inattentive, not to say undevout, if he had not recalled the few details about individual apostles from such hearing or reading.


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