Table 2.

Comparison of the concentrations of amino acids present in the released crypt matrix fluid and symbiont cells from the E. scolopes light organ^*

Amino acid	Crypt matrix fluid		Symbiont cells (free + peptide), mM
	Free form†, mM	Peptide form‡, mM
Alanine	0.14	0.91	1.79
Arginine	ND	0.67	0.90
Aspartate + asparagine	0.06	1.49	2.08
Cysteine	ND	0.21	0.21
Glycine	0.16	1.21	0.80
Glutamate + glutamine	0.10	1.63	3.40
Histidine	ND	0.36	0.40
Isoleucine	0.12	0.58	0.94
Leucine	0.07	1.10	1.58
Lysine	0.04	1.11	1.44
Methionine	ND	0.67	0.90
Phenylalanine	0.03	0.59	0.86
Proline	ND	0.72	0.79
Serine	0.04	1.01	1.31
Threonine	ND	1.09	1.44
Tyrosine	0.03	0.48	0.69
Valine	0.09	0.77	1.26
Total	0.88	15.25	22.74

ND, Not detected (<0.01 mM). 

^*Representative values for the concentrations of amino acids present in released crypt contents. Values are calculated based on a 10-μl volume of collected crypt contents. These values may be underestimations because of a slight swelling of the matrix fluid upon its release. Tryptophan concentration was not determined in the analyses. 

^†Concentration of each amino acid present as free monomers in the sample. 

^‡Concentration of each amino acid present as peptides (i.e., oligopeptides and proteins) was calculated as the total amino acids minus the free monomers.