Studies on the Quantitative Incorporation of Sulphate Sulphur into Methionine, Cystine and Taurine in the Hen

Abstract

In troclrictionRcccnt investigations liavc clcmonstratccl that tlic proccsses of sulphur mctabolisiii in thc hen dilTcr in sevcr:il rcspects from tliosc occiirring in tlic nianirnal. It has been observed, for csamplc, that whcrcas mammals can apparently satisfy their physiological rcquirciiicnts for sulphatc ions l q tlic normal cataliolism of the sulpliurcontaining amino acids, growth rcsponscs to orally :idministcrctl sodium sulphatc h a w bccn dctccted in chicks fctl a purifictl clict clcvoicl of inorganic sulphur, (Gordon 6 Sizcr (1 O,?,?), ant1 Alachlin L! Pcarson (1956)). Alachlin and Pearson (loc. cit.) liavc suggcstcd that sincc in their cspcrimcnts sulphntc sulphur was not utilizctl for tlic syntlicsis of tlic sulpli~ir-containing airiino acids in amounts largc enough to suggcsl nutritional significancc, this growth rcsponsc may rcflcct a physiological requirement for sulphatc per sc.Anothcr interestiiig obscrvation lias bccn ni:itle regarding thc incorporation of dictary inorganic suiphur into organic compoun(1s. It is gencrally assumed that tlic incorporation of sulphatc sulphur into tlic sulphur-containin~:ir-containiii~ .amino acids and Ibvitaniins in inanimals rcsults from microbial activity in the alinientary canal, this proccss being very iiiiportant in ruminants (Anderson (1 9%). Kccncr and l'ccri (1953). and Iiul~vich (1 9S7)), but not in non-ruminants (Bostrom and &pist (1952) and I<ulwicli ef ctl; (1958)). However, llachlin el (11. (1953) with laying hcns and lfachlin and Pearson (loc. cit.) wit11 chicks have ~~rcscntcd evidcncc suggesting that on a sniall scale tlicsc Downloaded by [University of California Santa Barbara] at 14:49 10 June 2016 4 Y. C. SIASON, J. 0. IIANSEN A N D RIRSTES WEIDSERbirds can incorporate the sulphur atoms of sulphate ions into cystine, but not into methionine, without the involvement of micro-organisms.One of the principal differences between the hen and the mammal is the level of taurine i n their tissues. In the mammal, taurine is synthesized as a by-product of cysteine metabolism, and is largely escrcted unchanged in the urine or else conjugated with the bile acids as taurocholic acid. Usually, only small amounts of taurine are found in the tissues of these animals. On the other hand, Gordon and Sizer (loc. cit.) and hIachlin ant1 Pearson (loc. cit.) have observed large amounts of taurine in their birds, the latter authors suggesting that it "is possible that free taurine has some function other than as component of bile acids". Furthermore, Machlin ef al. (1955) and Lowe and Roberts (1955) hare noted that the chick embryo incorporates sulphate sulphur into taurine in large amounts, but cannot utilize it in the synthesis of cystine. Chapeville and Froniageot (1956, 1957) have suggested metabolic pathways for these processes.Very little is known ahout the physiological role of taurine in the hen. AIachlin and Pearson (1957) injected S35-labelled taurine into young chicks fed a diet slightly deficient in the sulphur-containing amino acids, and found that by ...

Factors Affecting Sulfate-Sulfur Utilization by the Young Chick

“…Several reports concerning sulfate contain results which support this finding, but the verification using crystalline amino acid diets has not been accomplished. Mason et al (1965) fed caecectomized hens and found that sulfate sulfur was incorporated into taurine, cysteic acid and cystine, but not into methionine. In their third experiment no response was observed when 0.16% methionine was added to the diet.…”

Choline, Methionine and Sulphate Interrelationships in Poultry Nutrition—A Review

“…Some research workers (Machlin et al, 1953(Machlin et al, , 1954Machlin and Pearson, 1956;Almquist, 1964;Mason et al, 1965) have suggested that since in several experiments sulphate sulphur was not utilized for the synthesis of the sulphur amino acids in amounts large enough to suggest nutritional significance, this growth response may reflect a physiological requirement for sulphate per se. However, Sasse and Baker (1974a) concluded from their experiments that there is no dietary requirement for sulphate per se since there was no response to sulphate in the presence of adequate SAA.…”

The Synthesis of Taurine from Sulfate III. Further Evidence for the Enzymatic Pathway in Chick Liver

“…I t has been reported that taurine may be synthesized de novo from inorganic sulfate (4)(5)(6)(7)(8). The utilization of inorganic sulfate requires its conversion to the active form, 3'phosphoadenosine-5'-phosphosul fa te ( PAPS ) , after which it is enzymatically transferred to a suitable acceptor molecule by PAPStransferase (EC 2.8.2) (9).…”