Quantitative dietary requirements for histadine in the saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (coleoptera, silvanidae)

Comp. Biochem. Physiol., 1969, Vol. 28, pp. 741 to 746. Pergamon Press. Printed in Great Britain

QUANTITATIVE DIETARY REQUIREMENTS FOR HISTIDINE IN THE SAW-TOOTHED GRAIN BEETLE, O R Y Z A E P H I L U S S U R I N A M E N S I S (L.) (COLEOPTERA, SILVANIDAE)* G. R. F. DAVIS Insect Ecology Section, Research Station, Research Branch, Canada Agriculture, Saskatoon, Canada

(Received 21 aTune1968) Abstract--1. Histidine is essential in the diet of Oryzaephilus surinamemis (L.), the optimal concentration being between 2"0 and 4"0 mg/g of diet. 2. Concentrations of dietary histidine of 5"0 and 6-0 mg/g were harmful to the larvae. 3. Addition of equimolecular amounts of glycine to maintain the diet isonitrogenous when histidine concentrations were reduced was harmful to the larvae. 4. Histidine could not be replaced in the diet for O. surinamensis by additional quantities of guanine. INTRODUCTION FOURTEEN immature insects were listed in a recent review as requiring a dietary source of histidine (House, 1965). Other workers have shown that Bombyx mori L. (Ito & Arai, 1965), Anthonomus grandis Boheman (Vanderzant, 1965) and Argyrotaenia velutinana (Walker) (Rock & King, 1967) also require histidine in the diet. Investigations using labelled glucose have confirmed the apparent universal need for dietary histidine in insects (Kasting et al., 1962; Pickett & Friend, 1965; Shyamala & Bhat, 1965; Kasting & McGinnis, 1966). In another investigation, dietary histidine was essential or useful for Tenebrio molitor L. only under certain circumstances (Leclercq & Lopez-Francos, 1964). In determinations of quantitative requirements for this amino acid, Tribolium confusum Duval required a minimum of 2.0 mg and an optimum of 6.0 mg/g of diet (Medici, 1964). The minimum requirement for histidine, based on fresh weights of larvae of Oryzaephihs surinamensis (L.) at 336 or 432 hr of age, was determined as 2.0 mg/g of diet (Medici, 1964). The lowest concentration of dietary histidine monohydrochloride considered optimal for B. mori was 5.0 mg/g of diet (Arai & Ito, 1967). Early work with O. surinamensis (Davis, 1956) seemed to agree with results obtained in the investigations with T. molitor (Leclercq & Lopez-Francos, 1964). * Contribution No. 313, Canada Agriculture Research Station, Saskatoon, Sask., Canada. 741

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G.R.F.

DAvis

R e m o v a l o f h i s t i d i n e t o g e t h e r w i t h a l a n i n e f r o m t h e d i e t in use at t h a t t i m e r e s u l t e d o n l y in d e c r e a s e d s u r v i v a l a n d in l e n g t h e n e d d e v e l o p m e n t p e r i o d ( D a v i s , 1956). H o w e v e r , t h a t d i e t c o n t a i n e d y e a s t R N A , r e c e n t l y s h o w n to c o n t a i n t r a c e a m o u n t s o f h i s t i d i n e in b o u n d f o r m ( D a v i s , 1967). T h i s is a r e p o r t on t h e q u a n t i t a t i v e d i e t a r y r e q u i r e m e n t s o f l a r v a e o f O. surinamensis for h i s t i d i n e , d e t e r m i n e d w i t h a h o l i d i c d i e t at 32 _+ 2°C a n d 75 + 5 p e r c e n t relative humidity. MATERIALS AND METHODS T h e components of the basic diet used in these investigations are given in Table 1. Six diets were prepared in which the L-histidine concentration was progressively reduced by TABLE 1--COMPOSITION OF THE BASICDIET USED TO DETERMINEDIETARYHISTIDINE REQUIREMENTS OF Oryzaephilus surinamensis (L.)*

Amino acids L-Arginine (free base) L-Aspartic acid L-Cystine L-Glutamic acid Glycine L-Histidine (free base)

L-Isoleucine L-Leucine L-Lysine monoHCl L-Methionine L-Phenylalanine L-Serine L-Threonine (allo free) L-Tryptophan L-Tyrosine L-Valine

mg/g 9"0 11-0 2"0 30"0 53"0 6"0 12'0 14"0 13.0 6"0 5"0 1"0 9"0 2"0 10"0 11"0

Other components

mg/g

Dextrin (bacteriological)t 725.0 McCollum-Davis' salt mixture, No. 185t 35.0 Cholesterol 3"7 Guanine, synthetic, M . A . 0"4 Cytosine, synthetic, M . A . 0"4 Putrescine diHCl, M . A . 0"2 Folic acid 0"2 Choline chloride 1"5 i-Inositol 1"5 p-Aminobenzoic acid 0"15 Niacin 0" 15 Ca pantothenate 0"15 Pyridoxine HC1 0-15 Riboflavin 0-15 Thiamine HCI 0-15 Biotint 1"0 x 10 -4 Vitamin Blot 1"2 x 10 -4 rrd/g Corn oil++ 0"01

* Mann Research Laboratories, Inc., New York, unless otherwise noted. All amino acids were of the M. A. grade. t Nutritional Biochemicals Corp., Cleveland, Ohio. ++Best Foods Division, T h e Canada Starch Co. Ltd., Montreal. 1.0 mg/g, so that the range of histidine concentrations in the diets was from 5"0 to 0"0 mg/g. Six other diets were prepared similarly, except that the nitrogen level was maintained at that of the basic diet by addition of equimolecular amounts of glycine. Two diets were prepared lacking histidine, to which was added 1"5 or 4"5 mg of additional guanine/g of diet, corresponding to 1"1 and 4"0 mg of histidine free base/g of diet, respectively. Newly hatched larvae of O. surinamensis were reared individually in tubes in two groups of fifty on each diet at 32 _+2°C and 75 _+5 per cent relative humidity. Tubes were checked

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DIETARY R E Q U I R E M E N T S FOR H I S T I D I N E I N S A W - T O O T H E D G R A I N BEETLE

every 24 h r to d e t e r m i n e survival, p u p a t i o n a n d a d u l t e m e r g e n c e . W h e n a d u l t e m e r g e n c e was c o m p l e t e d , two g r o u p s of t e n adults each were selected at r a n d o m f r o m each diet a n d were w e i g h e d to t h e n e a r e s t 0"1 mg. T h e average w e i g h t p e r a d u l t o n each diet was calculat e d f r o m these data. D a t a o n survival were analyzed b y t h e X2 test (Stanley, 1963) a n d o n rate of d e v e l o p m e n t b y D u n c a n ' s m u l t i p l e r a n g e test ( R o b i n s o n , 1959). Differences at t h e 5 p e r cent level of confidence were c o n s i d e r e d significant. RESULTS

Non-isonitrogenous diets Reduction of the concentration of dietary histidine did not affect the numbers of O. surinamensis surviving, until the diet was completely devoid of histidine (Table 2). However, the percentages of pupae becoming adults were lower with diets containing less than 4.0 mg of histidine/g than with the basic diet. Without dietary histidine, all larvae died without pupating by 1044 hr. TABLE 2--EFFECTS OF PROGRESSIVELY DELETING L-HISTIDINE IN A HOLIDIC DIET FOR Oryzaephilus surinamensis (L.) REARED INDIVIDUALLY FROM HATCHING IN TWO GROUPS OF 50 AT 32 _+2°C AND 75 + 5 PER CENT RELATIVE HUMIDITY H i s t i d i n e in diet (mg/g)

No. pupating

6"0 (basic) 5"0 4"0 3"0 2"0 1"0 0"0

Average time (hr _+ S.E.)

No. emerging

Average t i m e (hr + S.E.)

77 523 + 6 c 76 ( 9 9 % ) 78 517 + 7 b, c 78 ( 1 0 0 % ) 83 510 + 6 b, c 82 ( 9 9 % ) 84 492+5 b 81 ( 9 6 % ) * 85 487 + 5 a 78 ( 9 2 % ) * 76 485+8a 68(89%)* 0 - 5 0 % m o r t a l i t y before 324 h r ; 1 0 0 % b y

643 + 7 637 + 7 624 + 5 602 + 6 604 + 7 600+7 1044 h r

b b a, b a a a

35* 634+17 d 20*(57%)* 45* 619+16d 22*(49%)* 53* 634+11 d 29*(55%)* 14" 717 + 24 e 9*(64%)* 9* 857 + 3 5 f 2*(22%)* 0 - 5 0 % m o r t a l i t y before 324 h r ; 1 0 0 % b y

773+20d 732+13 c 771 + 1 4 d 847 + 28 e 912 + 6 0 f 492 h r

A v e r a g e wt. a d u l t (mg) 0'52 0'54 0"58 0"55 0"49 0"56

Isonitrogenous diets 5"0 4"0 3-0 2-0 1.0 0.0

0'35 0"46 0-38 0"37 0.25

L-Histidine replacedby guanine 0"0 + 1"5 m g guanine/g 0'0 + 4 " 5 m g guanine/g

0 - 5 0 % m o r t a l i t y before 324 h r ; 100°,~ b y 348 h r 0 - 1 0 0 % m o r t a l i t y before 324 h r

Values for average t i m e s followed b y t h e s a m e letter do n o t differ f r o m each o t h e r at t h e 5 p e r cent level of confidence. * Significantly different f r o m values o b t a i n e d w i t h t h e basic diet at t h e 5 p e r cent level of confidence.

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Development to the pupal stage was more rapid with diets containing 3-0, 2.0 and 1.0 mg of histidine/g than with the basic diet (Table 2). Similarly, the rate of development to adult emergence was more rapid with diets containing 3.0, 2.0 or 1.0 mg of histidine/g than with the basic diet. lsonitrogenous diets Fewer individuals of O. surinamensis pupated and fewer adults emerged with these diets than with the basic diet (Table 2). In contrast to larvae on the nonisonitrogenous diets, more individuals pupated on these diets with 4.0 mg (0.05 > P > 0.02) and 3.0 mg ( P < 0.01) of dietary histidine/g than with 5.0 mg/g. Also, fewer pupated with 2.0 or 1.0 mg of dietary histidine/g than with 5.0 mg/g ( P < 0.01). More adults emerged on a diet containing 3.0 mg of dietary histidine/g (0.05 > P > 0-02) and fewer on diets containing less than this amount (P < 0.01) than on the diet containing 5.0 mg/g. The percentage of emergent adults fell below that on the diet containing 5.0 mg of histidine/g only on the diet containing 1.0 mg/g ( P < 0.01). Total mortality occurred on the histidine-free diet as early as 492 hr. The rate of development on these diets decreased with decreasing concentrations of dietary histidine (Table 2). Guanine-substituted diets Guanine could not replace histidine free base in this diet for O. surinamensis (Table 2). With an equimolecular concentration of guanine corresponding to 1.1 mg of histidine free base/g of diet, O. surinamensis survived slightly longer than with a concentration corresponding to 4.0 mg of histidine free base/g. However, neither concentration of guanine was beneficial to this insect.

Adult weights Adults emerging from pupae formed on diets kept isonitrogenous with glycine appeared to weigh consistently less than those from pupae formed on the other diets (Table 2). However, the data were insufficient to show that the weights were influenced by the different compositions of the diets (P> 0.05). DISCUSSION The results of the present investigation indicate that dietary histidine is required for normal survival and rate of development of O. surinamensis. They corroborate and enlarge upon the dietary requirement for histidine suggested previously for O. surinamensis reared on a different diet at the same temperature and humidity (Davis, 1956). The liminal concentration of dietary histidine free base lay between 0-0 and 1-0 mg/g; the minimal, between 0.0 and 2.0 mg/g; and the optimal, between 2.0 and 4.0 mg/g of diet (Table 2). These results differ from those obtained for O. surinamensis with a diet of slightly different composition, based on fresh weights of larvae at 336 or 432 hr of age (Medici, 1964). In the latter investigation, some growth took place in the absence of dietary histidine and the optimal concentration

DIETARY REQUIREMENTS FOR HISTIDINE IN SAW-TOOTHED GRAIN BEETLE

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apparently lay between 3.0 and 6"0 mg/g of diet. Also, a concentration greater than 4.0 mg/g did not adversely affect O. surinamensis in that investigation (Medici, 1964). The optimal dietary concentration of histidine in the present work, however, approximated the concentration (5.0 rag/g) of histidine monohydrochloride which was optimal for B. mori (Arai & Ito, 1967). Further, the optimal concentration of histidine in this investigation was considerably less than the 6.0 mg/g required by T. confusum (Medici, 1964). The lack of survival of O. surinamends on a diet devoid of histidine (Table 2) showed that the trace quantities of this amino acid bound to yeast RNA were indeed sufficient for the slight survival and the slow development in the previous investigation (Davis, 1956). T h e deleterious effect of dietary histidine concentrations greater than optimal in the present work agrees with results obtained with excess amounts of this amino acid in the diet of B. mori (Arai & Ito, 1967). Previously, when amino acids were deleted from the diet for O. surinamensis, the diet was kept isonitrogenous with equimolecular quantities of glycine (Davis, 1959, 1961, 1962). T h e results of the present investigation indicate that such a practice can result in biased interpretations of effects of decreasing the concentration of a dietary amino acid (Table 2). Replacement of as little as 1.0 mg of histidine/g by an equivalent amount of glycine was harmful to O. surinamensis. This deleterious effect increased with increasing concentrations of dietary glycine. Excessive concentrations of dietary glycine have also been reported toxic for Calliphora erythrocephala (Meig.) (Sedee, 1956). Nevertheless, this effect of glycine did not mask the effects of dietary concentrations of histidine (Table 2). Histidine is implicated in biosynthesis of purines in many organisms (West & Todd, 1955). It may contribute to purine biosynthesis in insects, when sufficient quantities of these compounds are not present in the diet. This may explain its requirement under certain circumstances by T. molitor (Leclercq & Lopez-Francos, 1964). However, the present basic diet contained guanine at a concentration previously shown to be satisfactory for O. surinamensis (Davis, 1966). The role of dietary histidine in the metabolism of O. surinamensis must therefore be other than biosynthesis of purines. The failure of guanine to substitute for histidine in the diet of O. surinamensis (Table 2) also indicated that histidine is not used by this organism in the biosynthesis of purines. None of adenine, guanine or creatinine, nor a combination of these was able to replace histidine in the diet of the rat (Cox & Rose, 1926a), but DL-fl-4imidazolelactic acid could (Cox & Rose, 1926b). This implies that the same metabolic pathway may be operative in both organisms and that an investigation of the effects of the latter compound in the diet of O. surinamensis is warranted. Acknowledgement--The technical assistance of Mr. F. T. Eves is gratefully acknowledged.

REFERENCES ARAI N. & ITO T. (1967) Nutrition of the silkworm, Bombyx mori--XVI. Quantitative requirements for essential amino acids. Bull. seric, exp. Sta. 21,373-384.

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Cox G. J. & ROSE W. C. (1926a) Can purines, creatinine, or creatine replace histidine in the diet for purposes of growth ? ft. biol. Chem. 68, 769-780. Cox G. J. & ROSE W. C. (1926b) The availability of synthetic imidazoles in supplementing diets deficient in histidine. J. biol. Chem. 68, 781-799. DAVIS G. R. F. (1956) Amino acid requirements of Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae) for pupation. Can.ft. Zool. 34, 82-85. DAVIS G. R. F. (1959) Alanine and proline in the diet of larvae of Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae). Ann. eat. Soc. Am. 52, 164-167. DAVIS G. R. F. (1961) Sulfur-containing amino acids in the nutrition of the saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae). J. Nutr. 75, 275278. DAVIS G. R. F. (1962) Quantitative L-arginine requirements of larvae of the saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera, Silvanidae). J. lnsect Physiol. 8, 377-382. Davis G. R. F. (1966) Replacement of RNA in the diet of Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae) by purines, pyrimidines, and ribose. Can.ft. Zool. 44, 781-785. Davis G. R. F. (1967) Reassessment of some amino acid requirements of larvae of Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae). J. Nutr. 91, 255-260. HOUSE H. L. (1965) Insect nutrition. In The Physiology of the Insecta (Edited by ROCKSTEiN M.), Vol. 2, pp. 769-813. Academic Press, New York. ITO T. & A ~ I N. (1965) Nutrition of the silkworm, Bombyx mori--VIII. Amino acid requirements and nutritive effects of various proteins. Bull. seric, exp. Sta. 19, 345-373. KASTING R., DAVIS G. R. F. & McGINNIS A. J. (1962) Nutritionally essential and nonessential amino acids for the prairie grain wireworm, Ctenicera destructor Brown, determined with glucose-U-14C. J. Insect Physiol. 8, 589-596. KaSTINC R. & McGINNIS A. J. (1966) Amino acid requirements of Hypoderma boris (L.), determined with glucose-U-14C. Expl Parasit. 19, 249-253. LECLERCQJ. & LOPEz-FRaNCOS L. (1964) Nutrition protidique chez Tenebrio molitor L . - - V I . Essais de remplacement de la cas6ine par des m61anges artificiels d'acides amin6s. Archs int. Physiol. Biochim. 72, 276-296. MEDICI J. C. (1964) Nutritional studies, including quantitative amino acid and mineral requirements, with the flour beetle, Tribolium confusum (Dural). Ph.D. Thesis, Rutgers-The State University, New Brunswick, New Jersey. PICKETT C. • FRIEND W. G. (1965) The nutritionally essential amino acids of Rhodnius prolixus (St~il) determined with glucuose-U-14C. J. Insect Physiol. 11, 1617-1623. ROBINSON P. (1959) Tests of Significance for Use in Comparison of Several Means with Particular Reference to Duncan's Multiple Range Test. Canadian Dept. Agriculture Processed Publ. 4, Ottawa. ROCK G. C. & KING K. W. (1967) Qualitative amino acid requirements of the red-banded leaf roller, Argyrotaenia velutinana (Lepidoptera: Tortricidae). J. Insect Physiol. 13, 59-68. SEDEE P. D. J. W. (1956) Dietetic requirements and intermediary protein metabolism of the larva of Calliphora erythrocephala (Meig.). D.Sc. Thesis, University of Utrecht, The Netherlands. SHYAMALAM. B. & BHAT J. V. (1965) Essential amino acid requirements of the silkworm, Bombyx mori L. Indian J. Biochem. 2, 201-202. STANLEYJ. (1963) The Essence ofBiometry, p. 53. McGill University Press, Montreal. VANDERZANTE. S. (1965) Axenic rearing of the boll weevil on defined diets: amino acid, carbohydrate and mineral requirements, ft. Insect Physiol. 11, 659-670. WEST E. S. & TODD W. R. (1955) Textbook of Biochemistry, 2nd edn, p. 1109. Macmillan, New York.