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We analyzed the safety and immunogenicity of attenuated rabies virus vectors expressing simian-human immunodeficiency virus (SHIV)-1(89.6P) Env or simian immunodeficiency virus (SIV)(mac239) Gag in rhesus macaques. Four test macaques were immunized with both vaccine constructs, and 2 control macaques received an empty rabies vector. Seroconversion against rabies virus glycoprotein (G) and SHIV(89.6P) Env was detected after the initial immunization, but no cellular responses against SHIV antigens were observed. HIV/SIV-specific immune responses were not enhanced by boosts with the same vectors. Therefore, we constructed vectors expressing SHIV(89.6P) Env and SIV(mac239) Gag in which the rabies G was replaced with the G protein of vesicular stomatitis virus (VSV). Two years after initial immunization, a boost with the rabies-VSV G vectors resulted in SIV/HIV-specific immune responses. Upon challenge with SHIV(89.6P) test macaques controlled the infection, whereas control macaques had high levels of viremia and a profound loss of CD4(+) T cells, with 1 control macaque dying of an AIDS-like disease.

are presented in this report. Although the amino acid needs of some lactobacilli, particularly the strains suggested for use in microbiological assays, have been studied in considerable detail, the requirements of oral lactobacilli have been relatively neglected. In a general way, however, it is usually supposed that the amino acid requirements of lactobacilli from the mouth are probably as complex as those of lactobacilli used for assays or those from dairy and fermentation sources. Earlier attempts to cultivate oral lactobacilli in simple synthetic mediums uniformly met with failure. During the studies on vitamin requirements it became apparent that protein hydrolyzates were necessary to supply a number of amino acids and that it was advisable to supplement acid hydrolyzates with tryptophane and cystine. Aside from this recognition of the importance of a number of amino acids for oral lacto

In a previous publication1 it was reported that in a simple chemically defined medium, growth of a number of the gram-negative enteric bacteria, together with a few other miscellaneous types, was markedly retarded or completely inhibited by 5000 or 10,000 /xg per ml of nicotinic acid or nicotinamide. The medium was composed of ammonium phosphate, glucose, salts, and in some cases small amounts of one or two additional vitamins or amino acids

This report is an extension of an earlier study which dealt with certain unusual aspects of the growth response of Leuconostoc to nicotinic acid and related compounds. It was first reported by Johnson1 that Leuconostoc mesenteroides 9135, though requiring nicotinic acid, did not respond to ordinary amounts of nicotinamide or nicotinuric acid. It was found by the writers2 that of 6 Leuconostoc cultures which needed nicotinic acid for prompt growth in a casein digest medium, two of them failed to grow in the presence of nicotinamide, diphosphopyridine nucleotide (DPN), or triphosphopyridine nucleotide (TPN), while a third culture failed to grow in nicotinamide but grew promptly when DPN or TPN was supplied. Also, these 3 cultures did not respond to ordinary amounts of nicotinuric acid and methyl nicotinate, compounds which usually are utilized readily by other nicotinic acid requiring bacteria. The present work deals with certain aspects of the behavior of Leuconostoc not covered in our earlier report and includes also some tests with Streptococcus salivarius. The series of Leuconostoc cultures was extended to include additional representatives of the genus. A synthetic medium of amino acids and other definite compounds was used for this larger series of cultures in place of

which ferment glucose are also able, with a few exceptions, to ferment glucosamine with the production of acid or acid and gas when the amino sugar is incorporated in nutrient broth or other suitable medium (Meyer, 1913; Noble and Knacke, 1928; Koser and Saunders, 1933). Wedumi and Walker (1935) applied quantitative analysis to the study of 61 strains of bacteria representing 32 species and a few yeasts or yeastlike fungi. All bacteria which fermented glucose in indicator broth tests also utilized glucosamine. Apparently no lactobacilli were used in any of the studies cited above. More recently, glucosamine has been included in studies of glucose analogues with the idea that some of them might serve as antagonists of glucose metabolism and, by virtue of this and perhaps other properties, possibly act as tumorinhibiting agents. In a review of tissue culture nutrition Morgan (1958) mentions several reports of a deleterious effect exerted by glucosamine on human tumor cells in tissue culture and on mouse sarcoma 37 in tissue culture and in mice.

Basal medium.?The basal medium used was similar to that previously employed1 and consisted of 0.59k acid-hydrolyzed purified casein, 1^0 glucose, 1^0 sodium acetate ^J^O, and inorganic salts, including 0.2% phosphate; this was supplemented with 100 mg each of L-cystine, ltryptophane, L-hydroxyproline, DL-threonine and DL-serine, 10 mg each of adenine sulfate, guanine hydrochloride, thymine, hypoxanthine, and uracil per liter of medium. The purines and pyrimidines were added because their presence, along with the needed vitamins, results in speedier growth of many lactobacilli. The vitamins used for 1000 ml of medium were